Havar UNS R30004
Cobalt-base precipitation-hardening alloy. Hamilton Precision Metals nominal composition (wt %): Co 42.0, Cr 19.5, Ni 12.7, W 2.7, Mo 2.2, Mn 1.6, C 0.2, Fe balance
Also known as UNS R30004, Havar, Dynavar
Havar (UNS R30004) is a heat-treatable cobalt-base alloy.
Evidence level
2 of 5
Lab-measured
- 0Predicted only. No one has made it, or no measurement exists.
- 1Calculated. Only calculated or predicted values from sources.
- 2Lab-measured. Measured properties with their conditions stated.
- 3Space-relevant tests. Measured in conditions relevant to space, such as vacuum or atomic oxygen.
- 4Ground-qualified. Qualified for an application on the ground.
- 5Flown or field-proven. Flight or field results exist.
Strength when cold rolled and heat treated
330,000 psi tensile
Stiffness
29.5 x 10^6 psi
Strength kept at 950 °F
75 % of room temperature strength
Recipe, share of the weight
- Co 42%Cobalt
- Cr 19.5%Chromium
- Ni 12.7%Nickel
- W 2.7%Tungsten
- Mo 2.2%Molybdenum
- Mn 1.6%Manganese
- C 0.2%Carbon
- Fe not statedIron
Best for
Thin, high-strength springs, diaphragms and foil windows that must stay non-magnetic and resist corrosion in mild acids and seawater
Weakest at
Ductility once age hardened: cold rolled and heat treated strip elongates only 1 % in 2 in, and boiling 96 % sulfuric acid attacks it at 273.76 mils per year
Risk at a glance
- People Low. Mostly a processing hazard
- If it fails Severe. Attack by boiling strong acids
- Corrosion Severe. Severe corrosion: 273.76 mils per year unwelded and 267.16 mils per year welded.
Quick facts: UNS R30004
| Property | Value | Basis |
|---|---|---|
| Density | 8.3 g/cm³ | 1 sourced value |
| Yield strength | 483 to 2,068 MPa | 3 sourced values across conditions |
| Tensile strength | 965 to 2,275 MPa | 4 sourced values across conditions |
| Young's modulus | 203 GPa | 1 sourced value |
| Thermal conductivity | 13 to 14.7 W/(m·K) | 2 sourced values across conditions |
| Thermal expansion (CTE) | 12.5 ppm/K | 1 sourced value |
| Melting point | 1,480 °C | 1 sourced value |
| Electrical resistivity | 9.2e-7 Ω·m | 1 sourced value |
What is the density of Havar (UNS R30004)?
Havar (UNS R30004) has a density of 8.3 g/cm³. The source and test conditions are listed in the properties table on this page.
What is the thermal conductivity of Havar (UNS R30004)?
Havar (UNS R30004) has a thermal conductivity of 13 to 14.7 W/(m·K). The range covers 2 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What is the coefficient of thermal expansion of Havar (UNS R30004)?
Havar (UNS R30004) has a coefficient of thermal expansion of 12.5 ppm/K. The source and test conditions are listed in the properties table on this page.
What is the melting point of Havar (UNS R30004)?
Havar (UNS R30004) has a melting point of 1,480 °C. The source and test conditions are listed in the properties table on this page.
What is the yield strength of Havar (UNS R30004)?
Havar (UNS R30004) has a yield strength of 483 to 2,068 MPa. The range covers 3 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.
What are the other names and codes for Havar (UNS R30004)?
Havar (UNS R30004) is also written as UNS R30004, Havar, Dynavar. Each code is printed in the source listed beside it in the designations table.
What is Havar (UNS R30004) used for?
Uses recorded in the sources include Power springs; Metal diaphragms for burst discs; Gap spacers in magnetic heads.
Why it exists
Havar is a cobalt-base alloy that Hamilton Precision Metals says combines very high strength with excellent corrosion resistance and non-magnetic behaviour. Its cold rolled and heat treated strip reaches 330,000 psi tensile and 300,000 psi yield. Hamilton lists power springs, metal diaphragms for sensors and burst discs, magnetic-head gap spacers and nuclear-physics target foils among its uses, and the arXiv paper describes its use as the entrance foil of F-18 cyclotron targets. The sources read here give no spacecraft flight record.
Where it's used
Mechanical springs
Hamilton lists power springs among the applications that have included Havar.
Diaphragms and burst discs
Hamilton lists metal diaphragms for aerospace sensors and for burst discs.
Magnetic heads
Hamilton lists gap spacers in magnetic heads.
F-18 cyclotron target window
The arXiv paper describes Havar foils as the entrance window for proton beams into enriched water for F-18 production.
Recipe
Cobalt-base precipitation-hardening alloy. Hamilton Precision Metals nominal composition (wt %): Co 42.0, Cr 19.5, Ni 12.7, W 2.7, Mo 2.2, Mn 1.6, C 0.2, Fe balance
Havar is a cobalt-base alloy of cobalt, chromium, nickel, tungsten, molybdenum, manganese and carbon, with iron as the balance (Hamilton nominal composition, wt %). The sources read here do not describe how the alloy is melted or how the strip is made.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Cobalt Co | 42% | Main element. Hamilton calls Havar a cobalt-base alloy. |
| Chromium Cr | 19.5% | Major alloying element. The sources give it no separate role. |
| Nickel Ni | 12.7% | Alloying element. The sources give it no separate role. |
| Tungsten W | 2.7% | Alloying element. The sources give it no separate role. |
| Molybdenum Mo | 2.2% | Alloying element. The sources give it no separate role. |
| Manganese Mn | 1.6% | Alloying element. The sources give it no separate role. |
| Carbon C | 0.2% | Minor element, limited in the nominal composition. |
| Iron Fe | not stated | Balance element. Hamilton gives iron as the balance, so no share is printed. |
Weight shares are as printed in the sources.
What it can do
Strength when cold rolled and heat treated
330,000 psi tensile
measured
Cold rolled and heat treated Havar gives 330,000 psi tensile and 300,000 psi yield strength, as typical values in the Hamilton datasheet.
Stiffness
29.5 x 10^6 psi
measured
The modulus of elasticity in tension is 29.5 x 10^6 psi, as printed in the Hamilton datasheet.
Strength kept at 950 °F
75 % of room temperature strength
measured
Hamilton says the alloy retains 75 % of its room temperature strength up to 950 °F.
How it compares
In Hamilton's 96 h test in boiling 10 % sulfuric acid, Havar corrodes at 9.79 mils per year, against 850 - 2400 for 316L and 20 - 30 for C-276 printed in the same row. In boiling 1 % hydrochloric acid, Havar corrodes at 237.79 mils per year, against 0.2 - 2 for C-276. The comparison rows below use density, thermal conductivity and thermal expansion from the other profiles. The tests differ in form and condition, so read them as examples, not a ranking.
The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.
| Measurement | UNS R30004 | UNS R30605 | UNS R30003 |
|---|---|---|---|
| Thermal behavior and safety | |||
| Melting point (approximate) | 1480 °C2 | 1329 to 1410 °C | no data |
| Thermal conductivity, datasheet | 13 W/(m·K)5 | 9.4 W/m·K | 12.5 W/(m.K) |
| Thermal conductivity at 23 °C, paper | 14.7 W/(m·K)6 | 9.4 W/m·K | 12.5 W/(m.K) |
| Lifetime and stability | |||
| Strength retained at 950 °F, share of room-temperature strength | 75 %14 | no data | no data |
| Physical and electrical | |||
| Density | 0.3 lb/in31 | 9.13 g/cm³ | 8.3 g/cm³ |
| Electrical resistivity at room temperature | 92 µΩ·cm3 | 89 µΩ·cm | 95 uOhm.cm |
| Hardness, annealed | 25 HRC13 | 25 to 35 HRC | no data |
| Hardness, cold rolledTypical value printed in the Hamilton datasheet | 50 HRC | 25 to 35 HRC | no data |
| Hardness, cold rolled and heat treatedTypical value printed in the Hamilton datasheet | 60 HRC | 25 to 35 HRC | no data |
| Other measurements | |||
| Coefficient of thermal expansion, 0 to 50 °C | 12.5 µm/m·°C4 | 14.4 µm/m·°C | 12.5 10-6/K |
| Modulus of elasticity in tension | 29.5 psi x 10^67 | 225 GPa | 215 GPa |
| Yield strength (0.2 % offset), annealed | 70000 psi8 | > 379 MPa | 1800 MPa |
| Yield strength (0.2 % offset), cold rolledTypical value printed in the Hamilton datasheet | 2.5×10^5 psi9 | > 379 MPa | 1800 MPa |
| Yield strength (0.2 % offset), cold rolled and heat treatedTypical value printed in the Hamilton datasheet | 3×10^5 psi10 | > 379 MPa | 1800 MPa |
| Tensile strength, annealedTypical value printed in the Hamilton datasheet | 1.4×10^5 psi | > 896 MPa | 120 ksi |
| Tensile strength, cold rolledTypical value printed in the Hamilton datasheet | 2.7×10^5 psi | > 896 MPa | 120 ksi |
| Tensile strength, cold rolled and heat treatedTypical value printed in the Hamilton datasheet | 3.3×10^5 psi | > 896 MPa | 120 ksi |
| Tensile strength quoted in paper | 1860 MPa11 | > 896 MPa | 120 ksi |
| Elongation in 2 in, annealedTypical value printed in the Hamilton datasheet | 40 %12 | 51 % | no data |
| Elongation in 2 in, cold rolledTypical value printed in the Hamilton datasheet | 1 % | 51 % | no data |
| Elongation in 2 in, cold rolled and heat treatedTypical value printed in the Hamilton datasheet | 1 % | 51 % | no data |
Why choose it, and why not
Good for
- Springs and diaphragms: 330,000 psi tensile strength in the cold rolled and heat treated condition, as Hamilton's typical value.
- Non-magnetic parts: Hamilton lists magnetic attraction as none.
- Seawater: Hamilton's test shows no pitting or general attack after 720 h at 86 °F.
Watch out for
- Ductility: the cold rolled and heat treated strip elongates 1 % in 2 in.
- Strong boiling acids: 96 % sulfuric acid gives 273.76 mils per year in Hamilton's test.
- Welding and grinding fumes can contain hexavalent chromium, according to the ATI sheet for a related cobalt alloy.
- No Havar-specific SDS, no flight record and no ASTM, AMS or EN specification number were found in this run.
Havar is a strong, non-magnetic cobalt-base alloy, and Hamilton's datasheet and corrosion tests support its use in springs, diaphragms and thin foils. Its ductility after age hardening is low, and boiling strong acids attack it hard. The sources read here show no spacecraft flight record.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Other names and standards
The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.
| System | Codes |
|---|---|
| UNS | R30004 |
| Trade name | Havar, Dynavar (original name) |
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Density | Typical value printed in the Hamilton Precision Metals Havar technical data sheet, Physical Properties table. Footnote 2 says the values guide alloy selection and are not a guarantee of minimum or maximum. Converted to g/cm3 on import. | unit in source 0.300 lbs/cu.in.temperature not stated | — |
| 2 | Melting point (approximate) | Approximate melting point printed in the Hamilton datasheet | unit in source 1480°Cbasis approximate, as printed | — |
| 3 | Electrical resistivity at room temperature | Typical value printed in the Hamilton datasheet, Physical Properties table | unit in source 92 Microhm·cmtemperature room temperature (R.T.) as printed | — |
| 4 | Coefficient of thermal expansion, 0 to 50 °C | Typical value printed in the Hamilton datasheet. 12.5 x 10-6/°C is the same as 12.5 µm/m·°C. | temperature 0 to 50 °Cunit in source 12.5 x 10-6/°C | — |
| 5 | Thermal conductivity, datasheet | Typical value printed in the Hamilton datasheet, Physical Properties table (printed as W/m·K) | unit in source 13.0 W/m·Ktemperature not stated | — |
| 6 | Thermal conductivity at 23 °C, paper | Value quoted in the introduction of an arXiv paper. The passage gives no test method. It differs from the Hamilton value of 13.0 W/(m·K), and both are recorded. | temperature 23 °Cunit in source 14.7 Wm-1K-1 at 23 °Cform not stated | — |
| 7 | Modulus of elasticity in tension | Typical value printed in the Hamilton datasheet. Converted to GPa on import from psi. | unit in source 29.5 x 10^6 PSItemperature not stated | — |
| 8 | Yield strength (0.2 % offset), annealed | Typical value printed in the Hamilton datasheet. Footnote 1 says values may be adjusted by process control. | temper annealedmeasure 0.2 % offsetunit in source 70,000 PSI | — |
| 9 | Yield strength (0.2 % offset), cold rolled | — | temper cold rolledmeasure 0.2 % offsetunit in source 250,000 PSI | — |
| 10 | Yield strength (0.2 % offset), cold rolled and heat treated | — | temper cold rolled and heat treatedmeasure 0.2 % offsetunit in source 300,000 PSI | — |
| 11 | Tensile strength quoted in paper | Value quoted in the introduction of an arXiv paper. The passage gives no temper or test method, so it is not matched to a Hamilton condition. | temper not statedunit in source 1860 MPa | — |
| 12 | Elongation in 2 in, annealed | — | temper annealedgauge 2 innote in source measured elongation is less for thickness down to 0.002 in | — |
| 13 | Hardness, annealed | Typical value printed in the Hamilton datasheet. Hardness is a short name because it is not in the canonical list. | temper annealedprinted as RC 25 | — |
| 14 | Strength retained at 950 °F, share of room-temperature strength | Statement in the Hamilton datasheet. Figure 1 that it refers to is not readable in the PDF text, so only this statement is recorded. strength_retention is a short name because it is not in the canonical list. | temperature 950 °Freference room temperature strengthunit in source 75% of room temperature strength up to 950°F | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| 10 % sulfuric acid at 150 °F for 96 h | low | Low uniform corrosion: 1.01 mils per year unwelded and 0.99 mils per year welded.1 |
| 10 % sulfuric acid at boiling for 96 h | moderate | Moderate corrosion: 9.79 mils per year unwelded and 10.28 mils per year welded.2 |
| 96 % sulfuric acid at 150 °F for 96 h | moderate | Moderate corrosion: 29.91 mils per year unwelded and 33.04 mils per year welded.3 |
| 96 % sulfuric acid at boiling for 96 h | severe | Severe corrosion: 273.76 mils per year unwelded and 267.16 mils per year welded.4 |
| 1 % hydrochloric acid at boiling for 96 h | severe | Severe corrosion: 237.79 mils per year unwelded and 248.69 mils per year welded.5 |
| 50 % sodium hydroxide at boiling for 96 h | moderate | Moderate corrosion: 7.49 mils per year unwelded and 7.55 mils per year welded.6 |
| 86 % phosphoric acid at 150 °F for 96 h | low | Low corrosion: 1.02 mils per year unwelded and welded.7 |
| Mixed acid-chloride (11.5 % H2SO4, 1.2 % HCl, 1 % CuCl2, 1 % FeCl3) at 122 °F for 24 h | moderate | No pitting, with uniform attack at 17 mils per year.8 |
| Ferric chloride pitting (ASTM G-48 Method A) at 68, 104 and 140 °F for 72 h | low | Resistant to pitting.9 |
| Ferric chloride crevice corrosion (ASTM G-48 Method B) at 68, 104 and 140 °F for 72 h | severe | Severe crevice attack.10 |
| Seawater at 86 °F for 720 h | low | No pitting or general attack.11 |
| Seawater crevice corrosion at 86 °F for 720 h | severe | Perforation at the crevice site, for welded and unwelded samples.12 |
| Sulfide stress cracking (NACE MR0175) | low | Acceptable for use in sour environments at 35 HRC maximum.13 |
| Pitting or crevice corrosion of surgical implants (ASTM F-746) at 98.6 °F | low | Critical crevice potential above +0.8 V (SCE) after 600 grit polish and passivation.14 |
| Proton-irradiated enriched water in pressurised F-18 cyclotron targets | moderate | Bare Havar releases a wide variety of radionuclidic and chemical impurities.15 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | 10 % sulfuric acid at 150 °F for 96 h | Hamilton's corrosion test on 0.045 in strand annealed strip (96 h) printed 1.01 mils/year (0.03 mm/year) for unwelded samples and 0.99 mils/year (0.03 mm/year) for welded samples. | temperature 150 °Fduration 96 hsample 0.045 in strip, strand annealed, HRB 91basis rating grouped by the assistant from the printed mils/year: under 5 low, 5 to 50 moderate, over 50 severe |
| 2 | 10 % sulfuric acid at boiling for 96 h | The same table prints 9.79 mils/year (0.25 mm/year) unwelded and 10.28 mils/year (0.26 mm/year) welded. The comparative columns print 850 - 2400 mils/year for 316L and 20 - 30 mils/year for C-276 in this row. | temperature boilingduration 96 hbasis rating grouped by the assistant from the printed mils/year |
| 3 | 96 % sulfuric acid at 150 °F for 96 h | Hamilton prints 29.91 mils/year (0.76 mm/year) for unwelded and 33.04 mils/year (0.84 mm/year) for welded samples over 96 h. No comparative figures are printed for this row. | temperature 150 °Fduration 96 hbasis rating grouped by the assistant from the printed mils/year |
| 4 | 96 % sulfuric acid at boiling for 96 h | Hamilton prints 273.76 mils/year (6.96 mm/year) unwelded and 267.16 mils/year (6.79 mm/year) welded. The comparative columns print 560 for 316L and >200 for C-276. | temperature boilingduration 96 hbasis rating grouped by the assistant from the printed mils/year |
| 5 | 1 % hydrochloric acid at boiling for 96 h | Hamilton prints 237.79 mils/year (6.05 mm/year) unwelded and 248.69 mils/year (6.32 mm/year) welded. The C-276 comparative column prints 0.2 - 2 mils/year, and the 316L column is blank for this row. | temperature boilingduration 96 hbasis rating grouped by the assistant from the printed mils/year |
| 6 | 50 % sodium hydroxide at boiling for 96 h | Hamilton prints 7.49 mils/year (0.19 mm/year) unwelded and 7.55 mils/year (0.19 mm/year) welded. The C-276 comparative column prints 2-4 mils/year. | temperature boilingduration 96 hbasis rating grouped by the assistant from the printed mils/year |
| 7 | 86 % phosphoric acid at 150 °F for 96 h | Hamilton prints 1.02 mils/year (0.03 mm/year) for both unwelded and welded samples. The comparative columns print 1000 for 316L and 20 for C-276. | temperature 150 °Fduration 96 hbasis rating grouped by the assistant from the printed mils/year |
| 8 | Mixed acid-chloride (11.5 % H2SO4, 1.2 % HCl, 1 % CuCl2, 1 % FeCl3) at 122 °F for 24 h | Hamilton's pitting test in this mixed acid reports no pitting and uniform attack at a corrosion rate of 17 mils/year, for unwelded and welded samples. | temperature 122 °Fduration 24 hbasis rating grouped by the assistant from the printed rate of 17 mils/year |
| 9 | Ferric chloride pitting (ASTM G-48 Method A) at 68, 104 and 140 °F for 72 h | Hamilton prints Resistant to pitting for this test. The table does not pair this result with each temperature, so it is recorded for the test group. | temperature 68, 104 and 140 °Fduration 72 hbasis printed result, not a rate |
| 10 | Ferric chloride crevice corrosion (ASTM G-48 Method B) at 68, 104 and 140 °F for 72 h | Hamilton prints Severe Crevice Attack for this test. The table does not pair this result with each temperature. | temperature 68, 104 and 140 °Fduration 72 hbasis printed result, not a rate |
| 11 | Seawater at 86 °F for 720 h | Hamilton prints No Pitting or General Attack for both unwelded and welded samples after 720 h in seawater at 86 °F. | temperature 86 °Fduration 720 hbasis printed result, not a rate |
| 12 | Seawater crevice corrosion at 86 °F for 720 h | Hamilton prints Perforation at Crevice Site for both unwelded and welded samples after 720 h at 86 °F. | temperature 86 °Fduration 720 hbasis printed result, not a rate |
| 13 | Sulfide stress cracking (NACE MR0175) | Hamilton prints Acceptable for use in Sour Environments for sulfide stress cracking by NACE MR0175, with 35 HRC max. in the sample condition column. | basis printed result, not a ratelimit 35 HRC max. |
| 14 | Pitting or crevice corrosion of surgical implants (ASTM F-746) at 98.6 °F | Hamilton prints the critical crevice potential as greater than +0.8 V (SCE) for a 600 grit polish with passivation. Its electrolyte is 0.9 % NaCl in distilled water at pH 7.0. | temperature 98.6 °Fsurface 600 grit polish plus passivationelectrolyte 0.9 % NaCl in distilled water, pH 7.0 |
| 15 | Proton-irradiated enriched water in pressurised F-18 cyclotron targets | The arXiv paper says the main disadvantage of Havar as an entrance foil is a wide variety of radionuclidic and chemical impurities generated under proton irradiation of water. It says a sputtered niobium coating on Havar reduced long-lived ionic impurities more than ten times, citing an earlier study. The paper gives no measured rate for bare Havar. | basis qualitative for bare Havar. The tenfold figure is quoted from an earlier study and was not measured in this paper.pressure pressurised, as stated in the paper |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The hazards in the sources come mainly from dust, fume and skin contact during processing. Cobalt is a sensitiser, and welding or grinding can release chromium VI.
- Solid product
- The ATI family sheet for cobalt alloy FRP002 says the product is an article that does not present a hazard to health by inhalation or ingestion, but it still lists classes such as carcinogenicity category 1B and skin sensitisation category 1.
- Dust and fume
- Welding, grinding, buffing and polishing can release hexavalent chromium, which the ATI sheet says may cause lung, nasal and sinus cancer. Fine particles can also form combustible dust.
- Sensitisation
- PubChem's aggregated cobalt data lists H317 and H334, which mean an allergic skin reaction and allergy or breathing difficulties if inhaled. The Havar datasheet gives no classification of its own.
If it fails
The failure routes in the sources are about forming, strong acids, crevices and proton-beam impurities. The sources report no measured service failure in space.
- Low ductility
- The cold rolled and heat treated strip elongates 1 % in 2 in, so bends are made before age hardening, with a radius of 8 times the thickness.
- Acid attack
- Boiling 96 % sulfuric acid gives 273.76 mils per year in Hamilton's 96 h test, and boiling 1 % hydrochloric acid gives 237.79 mils per year.
- Crevices
- Hamilton's seawater test shows no pitting or general attack after 720 h at 86 °F, but the crevice test perforates at the crevice site.
- Impurities
- According to the arXiv paper, bare Havar entrance foils release radionuclidic and chemical impurities in proton-irradiated water.
Handling and storage
- Forming
- Bend cold rolled Havar with a 90 degree radius of 8 times the thickness before age hardening.
- Heat treatment
- Heat treating at 1000 °F after 80 % cold work gives the ultimate endurance life, according to Hamilton.
- Dust control
- Keep fine dust from grinding and polishing away from ignition sources, and prevent dust build-up.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Low ductility after age hardeningmoderate severity | Bending or forming cold rolled and heat treated stripHamilton prints 1 % elongation in 2 in for the cold rolled and heat treated condition, against 40 % annealed. It asks for forming before age hardening, with a 90 degree bend radius of 8 times the thickness. |
| Attack by boiling strong acidscritical severity | Contact with boiling 96 % sulfuric acid or boiling 1 % hydrochloric acidHamilton's 96 h tests give 273.76 mils/year in boiling 96 % sulfuric acid and 237.79 mils/year in boiling 1 % hydrochloric acid. Both are above the 50 mils/year line used for a severe rating in this profile. |
| Crevice perforation in seawatercritical severity | A crevice in seawater at 86 °F for 720 hHamilton prints perforation at the crevice site for unwelded and welded samples, while the seawater test without a crevice shows no pitting or general attack. |
| Impurity release from entrance foils in proton beamsmoderate severity | Proton irradiation of enriched water in an F-18 targetThe arXiv paper says bare Havar generates a wide variety of radionuclidic and chemical impurities under this irradiation, which is why coated foils are studied. |
Handling and storage
- Forming cold rolled Havar requires a large radius (90 degree bend, 8 times the thickness) before age hardening.
- The ultimate endurance life is achieved by heat treating the alloy at 1000 °F after 80 % cold work, according to Hamilton.
- Hamilton says joining can be done by welding and soldering. No welding procedure or weld strength value is given in the sources read.
- Fine particles from grinding, buffing or polishing can form combustible dust-air mixtures. Keep them away from heat, sparks and flame, and prevent dust build-up.
- Wear protective gloves and use personal protective equipment as required when handling.
Mitigations
- The arXiv paper cites an earlier study in which a sputtered niobium coating on Havar entrance foils cut long-lived ionic impurities by more than ten times.
Supply and geography
How common the raw materials are and where they come from.
Cobalt (main element, 42.0 % nominal)
- Top producers (2025)
- Congo (Kinshasa) 73%, Indonesia 14%
- Recycling
- USGS: in 2025, cobalt content of purchased scrap represented 25% of estimated cobalt consumption. USGS also says 51% of cobalt consumed in the United States went into superalloys, mainly for aircraft gas turbine engines.
- Substitutes
- USGS: depending on the application, substitution for cobalt could result in a loss in product performance or increased cost.; USGS: potential substitutes in other applications include nickel-base alloys or ceramics in jet engines.
Chromium (19.5 % nominal)
- Top producers (2025)
- South Africa 45.1%, Turkey 17.6%, Kazakhstan 13.7%, India 5.9%
- Recycling
- USGS: in 2025, recycled chromium in reported stainless-steel scrap receipts accounted for 21% of apparent consumption.
- Substitutes
- USGS: chromium has no substitute in stainless steel, the leading end use, or in superalloys, the major strategic end use.
Documents
Datasheets, safety data sheets, papers and standards you can open.
Full record
The complete spore, as stored. Free to reuse under CC-BY-4.0. Images keep the licence shown with each one.
Show the full YAML
spore: profile
id: havar
spore_version: 0.2
family: cobalt-alloys
name: Havar
abbreviation: UNS R30004
role: heat-treatable cobalt-base alloy for high-strength springs, pressure diaphragms and thin foil windows
category: metals
type: nickel-superalloys
summary: |
Havar (UNS R30004) is a heat-treatable cobalt-base alloy. Hamilton Precision Metals gives its nominal composition as 42.0 % cobalt, 19.5 % chromium, 12.7 % nickel, 2.7 % tungsten, 2.2 % molybdenum, 1.6 % manganese and 0.2 % carbon, with iron as the balance. Its typical cold rolled and heat treated strength is 330,000 psi tensile and 300,000 psi yield, and its density is 0.300 lbs/cu.in. The alloy is non-magnetic. The Hamilton datasheet lists power springs, metal diaphragms for aerospace sensors and burst discs, gap spacers in magnetic heads and target foils in nuclear physics as applications. An arXiv paper on F-18 cyclotron targets describes Havar foils as the entrance window for a proton beam into enriched water.
best_for: Thin, high-strength springs, diaphragms and foil windows that must stay non-magnetic and resist corrosion in mild acids and seawater
weakest_at: 'Ductility once age hardened: cold rolled and heat treated strip elongates only 1 % in 2 in, and boiling 96 % sulfuric acid attacks it at 273.76 mils per year'
identity:
formula: 'Cobalt-base precipitation-hardening alloy. Hamilton Precision Metals nominal composition (wt %): Co 42.0, Cr 19.5, Ni 12.7, W 2.7, Mo 2.2, Mn 1.6, C 0.2, Fe balance'
source: hpm-havar-datasheet
where: Technical Data sheet, Nominal Composition table (title block HAVAR UNS R30004)
designations:
- system: UNS
code: R30004
source: hpm-havar-datasheet
where: Availability paragraph (the material corresponds to UNS R30004) and title block
- system: Trade name
code: Havar
source: hpm-havar-datasheet
where: Title block (registered trademark of Hamilton Precision Metals)
- system: Trade name
code: Dynavar
note: original name
source: wiki-havar-alloy
where: History section (originally developed as Dynavar)
tags:
environments: []
stresses: []
applications:
- mechanisms
- electronics-and-chips
- propulsion-and-tanks
- radiation-shielding
properties:
- benchmark: density
label: Density
value: 0.3
unit: lb/in3
scope: material
conditions:
unit_in_source: 0.300 lbs/cu.in.
temperature: not stated
method: Typical value printed in the Hamilton Precision Metals Havar technical data sheet, Physical Properties table. Footnote 2 says the values guide alloy selection and are not a guarantee of minimum or maximum. Converted to g/cm3 on import.
status: ground
source: hpm-havar-datasheet
where: Technical Data, Physical Properties table, row Density
- benchmark: melting_point
label: Melting point (approximate)
value: 1480
unit: °C
scope: material
conditions:
unit_in_source: 1480°C
basis: approximate, as printed
method: Approximate melting point printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Physical Properties table, row Melting Point (Approx.)
- benchmark: electrical_resistivity
label: Electrical resistivity at room temperature
value: 92
unit: µΩ·cm
scope: material
conditions:
unit_in_source: 92 Microhm·cm
temperature: room temperature (R.T.) as printed
method: Typical value printed in the Hamilton datasheet, Physical Properties table
status: ground
source: hpm-havar-datasheet
where: Physical Properties table, row Electrical Resistivity @ R.T.
- benchmark: cte
label: Coefficient of thermal expansion, 0 to 50 °C
value: 12.5
unit: µm/m·°C
scope: material
conditions:
temperature: 0 to 50 °C
unit_in_source: 12.5 x 10-6/°C
method: Typical value printed in the Hamilton datasheet. 12.5 x 10-6/°C is the same as 12.5 µm/m·°C.
status: ground
source: hpm-havar-datasheet
where: Physical Properties table, row Thermal Expansion Coefficient (0° to 50°C)
- benchmark: thermal_conductivity
label: Thermal conductivity, datasheet
value: 13
unit: W/(m·K)
scope: material
conditions:
unit_in_source: 13.0 W/m·K
temperature: not stated
method: Typical value printed in the Hamilton datasheet, Physical Properties table (printed as W/m·K)
status: ground
source: hpm-havar-datasheet
where: Physical Properties table, row Thermal Conductivity
- benchmark: thermal_conductivity
label: Thermal conductivity at 23 °C, paper
value: 14.7
unit: W/(m·K)
scope: material
conditions:
temperature: 23 °C
unit_in_source: 14.7 Wm-1K-1 at 23 °C
form: not stated
method: Value quoted in the introduction of an arXiv paper. The passage gives no test method. It differs from the Hamilton value of 13.0 W/(m·K), and both are recorded.
status: ground
source: arxiv-havar-niobium
where: Introduction, paragraph beginning High tensile strength (1860 MPa)
- benchmark: elastic_modulus
label: Modulus of elasticity in tension
value: 29.5
unit: psi x 10^6
scope: material
conditions:
unit_in_source: 29.5 x 10^6 PSI
temperature: not stated
method: Typical value printed in the Hamilton datasheet. Converted to GPa on import from psi.
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Modulus of Elasticity (Tension)
- benchmark: yield_strength
label: Yield strength (0.2 % offset), annealed
value: 70000
unit: psi
scope: material
conditions:
temper: annealed
measure: 0.2 % offset
unit_in_source: 70,000 PSI
method: Typical value printed in the Hamilton datasheet. Footnote 1 says values may be adjusted by process control.
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Yield Strength (0.2% Offset), column Annealed
- benchmark: yield_strength
label: Yield strength (0.2 % offset), cold rolled
value: 250000
unit: psi
scope: material
conditions:
temper: cold rolled
measure: 0.2 % offset
unit_in_source: 250,000 PSI
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Yield Strength (0.2% Offset), column Cold Rolled
- benchmark: yield_strength
label: Yield strength (0.2 % offset), cold rolled and heat treated
value: 300000
unit: psi
scope: material
conditions:
temper: cold rolled and heat treated
measure: 0.2 % offset
unit_in_source: 300,000 PSI
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Yield Strength (0.2% Offset), column Cold Rolled Heat Treated
- benchmark: ultimate_tensile_strength
label: Tensile strength, annealed
value: 140000
unit: psi
scope: material
conditions:
temper: annealed
unit_in_source: 140,000 PSI
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Ultimate Tensile Strength, column Annealed
- benchmark: ultimate_tensile_strength
label: Tensile strength, cold rolled
value: 270000
unit: psi
scope: material
conditions:
temper: cold rolled
unit_in_source: 270,000 PSI
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Ultimate Tensile Strength, column Cold Rolled
- benchmark: ultimate_tensile_strength
label: Tensile strength, cold rolled and heat treated
value: 330000
unit: psi
scope: material
conditions:
temper: cold rolled and heat treated
unit_in_source: 330,000 PSI
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Ultimate Tensile Strength, column Cold Rolled Heat Treated
- benchmark: ultimate_tensile_strength
label: Tensile strength quoted in paper
value: 1860
unit: MPa
scope: material
conditions:
temper: not stated
unit_in_source: 1860 MPa
method: Value quoted in the introduction of an arXiv paper. The passage gives no temper or test method, so it is not matched to a Hamilton condition.
status: ground
source: arxiv-havar-niobium
where: Introduction, paragraph beginning High tensile strength (1860 MPa)
- benchmark: elongation
label: Elongation in 2 in, annealed
value: 40
unit: '%'
scope: material
conditions:
temper: annealed
gauge: 2 in
note_in_source: measured elongation is less for thickness down to 0.002 in
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Elongation in 2 in, column Annealed
- benchmark: elongation
label: Elongation in 2 in, cold rolled
value: 1
unit: '%'
scope: material
conditions:
temper: cold rolled
gauge: 2 in
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Elongation in 2 in, column Cold Rolled
- benchmark: elongation
label: Elongation in 2 in, cold rolled and heat treated
value: 1
unit: '%'
scope: material
conditions:
temper: cold rolled and heat treated
gauge: 2 in
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Elongation in 2 in, column Cold Rolled Heat Treated
- benchmark: hardness_rockwell_c
label: Hardness, annealed
value: 25
unit: HRC
scope: material
conditions:
temper: annealed
printed_as: RC 25
method: Typical value printed in the Hamilton datasheet. Hardness is a short name because it is not in the canonical list.
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Hardness, column Annealed
- benchmark: hardness_rockwell_c
label: Hardness, cold rolled
value: 50
unit: HRC
scope: material
conditions:
temper: cold rolled
printed_as: RC50
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Hardness, column Cold Rolled
- benchmark: hardness_rockwell_c
label: Hardness, cold rolled and heat treated
value: 60
unit: HRC
scope: material
conditions:
temper: cold rolled and heat treated
printed_as: RC60
method: Typical value printed in the Hamilton datasheet
status: ground
source: hpm-havar-datasheet
where: Typical Mechanical Properties table, row Hardness, column Cold Rolled Heat Treated
- benchmark: strength_retention
label: Strength retained at 950 °F, share of room-temperature strength
value: 75
unit: '%'
scope: material
conditions:
temperature: 950 °F
reference: room temperature strength
unit_in_source: 75% of room temperature strength up to 950°F
method: Statement in the Hamilton datasheet. Figure 1 that it refers to is not readable in the PDF text, so only this statement is recorded. strength_retention is a short name because it is not in the canonical list.
status: ground
source: hpm-havar-datasheet
where: General Information paragraph, last sentence (Figure 1)
corrosion:
- environment: 10 % sulfuric acid at 150 °F for 96 h
headline: 'Low uniform corrosion: 1.01 mils per year unwelded and 0.99 mils per year welded.'
effect: Hamilton's corrosion test on 0.045 in strand annealed strip (96 h) printed 1.01 mils/year (0.03 mm/year) for unwelded samples and 0.99 mils/year (0.03 mm/year) for welded samples.
rating: low
conditions:
temperature: 150 °F
duration: 96 h
sample: 0.045 in strip, strand annealed, HRB 91
basis: 'rating grouped by the assistant from the printed mils/year: under 5 low, 5 to 50 moderate, over 50 severe'
source: hpm-havar-corrosion
where: Corrosion Rate table, row 10% H2SO4 at 150 °F
- environment: 10 % sulfuric acid at boiling for 96 h
headline: 'Moderate corrosion: 9.79 mils per year unwelded and 10.28 mils per year welded.'
effect: The same table prints 9.79 mils/year (0.25 mm/year) unwelded and 10.28 mils/year (0.26 mm/year) welded. The comparative columns print 850 - 2400 mils/year for 316L and 20 - 30 mils/year for C-276 in this row.
rating: moderate
conditions:
temperature: boiling
duration: 96 h
basis: rating grouped by the assistant from the printed mils/year
source: hpm-havar-corrosion
where: Corrosion Rate table, row 10% H2SO4 boiling, with comparative 316L and C-276 columns
- environment: 96 % sulfuric acid at 150 °F for 96 h
headline: 'Moderate corrosion: 29.91 mils per year unwelded and 33.04 mils per year welded.'
effect: Hamilton prints 29.91 mils/year (0.76 mm/year) for unwelded and 33.04 mils/year (0.84 mm/year) for welded samples over 96 h. No comparative figures are printed for this row.
rating: moderate
conditions:
temperature: 150 °F
duration: 96 h
basis: rating grouped by the assistant from the printed mils/year
source: hpm-havar-corrosion
where: Corrosion Rate table, row 96% H2SO4 at 150 °F
- environment: 96 % sulfuric acid at boiling for 96 h
headline: 'Severe corrosion: 273.76 mils per year unwelded and 267.16 mils per year welded.'
effect: Hamilton prints 273.76 mils/year (6.96 mm/year) unwelded and 267.16 mils/year (6.79 mm/year) welded. The comparative columns print 560 for 316L and >200 for C-276.
rating: severe
conditions:
temperature: boiling
duration: 96 h
basis: rating grouped by the assistant from the printed mils/year
source: hpm-havar-corrosion
where: Corrosion Rate table, row 96% H2SO4 boiling
- environment: 1 % hydrochloric acid at boiling for 96 h
headline: 'Severe corrosion: 237.79 mils per year unwelded and 248.69 mils per year welded.'
effect: Hamilton prints 237.79 mils/year (6.05 mm/year) unwelded and 248.69 mils/year (6.32 mm/year) welded. The C-276 comparative column prints 0.2 - 2 mils/year, and the 316L column is blank for this row.
rating: severe
conditions:
temperature: boiling
duration: 96 h
basis: rating grouped by the assistant from the printed mils/year
source: hpm-havar-corrosion
where: Corrosion Rate table, row 1% HCl boiling
- environment: 50 % sodium hydroxide at boiling for 96 h
headline: 'Moderate corrosion: 7.49 mils per year unwelded and 7.55 mils per year welded.'
effect: Hamilton prints 7.49 mils/year (0.19 mm/year) unwelded and 7.55 mils/year (0.19 mm/year) welded. The C-276 comparative column prints 2-4 mils/year.
rating: moderate
conditions:
temperature: boiling
duration: 96 h
basis: rating grouped by the assistant from the printed mils/year
source: hpm-havar-corrosion
where: Corrosion Rate table, row 50% NaOH boiling
- environment: 86 % phosphoric acid at 150 °F for 96 h
headline: 'Low corrosion: 1.02 mils per year unwelded and welded.'
effect: Hamilton prints 1.02 mils/year (0.03 mm/year) for both unwelded and welded samples. The comparative columns print 1000 for 316L and 20 for C-276.
rating: low
conditions:
temperature: 150 °F
duration: 96 h
basis: rating grouped by the assistant from the printed mils/year
source: hpm-havar-corrosion
where: Corrosion Rate table, row 86% H3PO4 at 150 °F
- environment: Mixed acid-chloride (11.5 % H2SO4, 1.2 % HCl, 1 % CuCl2, 1 % FeCl3) at 122 °F for 24 h
headline: No pitting, with uniform attack at 17 mils per year.
effect: Hamilton's pitting test in this mixed acid reports no pitting and uniform attack at a corrosion rate of 17 mils/year, for unwelded and welded samples.
rating: moderate
conditions:
temperature: 122 °F
duration: 24 h
basis: rating grouped by the assistant from the printed rate of 17 mils/year
source: hpm-havar-corrosion
where: Second table, row Pitting in Mixed Acid-Chloride
- environment: Ferric chloride pitting (ASTM G-48 Method A) at 68, 104 and 140 °F for 72 h
headline: Resistant to pitting.
effect: Hamilton prints Resistant to pitting for this test. The table does not pair this result with each temperature, so it is recorded for the test group.
rating: low
conditions:
temperature: 68, 104 and 140 °F
duration: 72 h
basis: printed result, not a rate
source: hpm-havar-corrosion
where: Second table, row FeCl3 Pitting by ASTM G-48 Method A
- environment: Ferric chloride crevice corrosion (ASTM G-48 Method B) at 68, 104 and 140 °F for 72 h
headline: Severe crevice attack.
effect: Hamilton prints Severe Crevice Attack for this test. The table does not pair this result with each temperature.
rating: severe
conditions:
temperature: 68, 104 and 140 °F
duration: 72 h
basis: printed result, not a rate
source: hpm-havar-corrosion
where: Second table, row FeCl3 Crevice Corrosion by ASTM G-48 Method B
- environment: Seawater at 86 °F for 720 h
headline: No pitting or general attack.
effect: Hamilton prints No Pitting or General Attack for both unwelded and welded samples after 720 h in seawater at 86 °F.
rating: low
conditions:
temperature: 86 °F
duration: 720 h
basis: printed result, not a rate
source: hpm-havar-corrosion
where: Second table, row Seawater
- environment: Seawater crevice corrosion at 86 °F for 720 h
headline: Perforation at the crevice site, for welded and unwelded samples.
effect: Hamilton prints Perforation at Crevice Site for both unwelded and welded samples after 720 h at 86 °F.
rating: severe
conditions:
temperature: 86 °F
duration: 720 h
basis: printed result, not a rate
source: hpm-havar-corrosion
where: Second table, row Seawater Crevice Corrosion
- environment: Sulfide stress cracking (NACE MR0175)
headline: Acceptable for use in sour environments at 35 HRC maximum.
effect: Hamilton prints Acceptable for use in Sour Environments for sulfide stress cracking by NACE MR0175, with 35 HRC max. in the sample condition column.
rating: low
conditions:
basis: printed result, not a rate
limit: 35 HRC max.
source: hpm-havar-corrosion
where: Second table, row Sulfide Stress Cracking by NACE MR0175
- environment: Pitting or crevice corrosion of surgical implants (ASTM F-746) at 98.6 °F
headline: Critical crevice potential above +0.8 V (SCE) after 600 grit polish and passivation.
effect: Hamilton prints the critical crevice potential as greater than +0.8 V (SCE) for a 600 grit polish with passivation. Its electrolyte is 0.9 % NaCl in distilled water at pH 7.0.
rating: low
conditions:
temperature: 98.6 °F
surface: 600 grit polish plus passivation
electrolyte: 0.9 % NaCl in distilled water, pH 7.0
source: hpm-havar-corrosion
where: Second table, row Pitting or Crevice Corrosion of Surgical Implants by ASTM F-746
- environment: Proton-irradiated enriched water in pressurised F-18 cyclotron targets
headline: Bare Havar releases a wide variety of radionuclidic and chemical impurities.
effect: The arXiv paper says the main disadvantage of Havar as an entrance foil is a wide variety of radionuclidic and chemical impurities generated under proton irradiation of water. It says a sputtered niobium coating on Havar reduced long-lived ionic impurities more than ten times, citing an earlier study. The paper gives no measured rate for bare Havar.
rating: moderate
conditions:
basis: qualitative for bare Havar. The tenfold figure is quoted from an earlier study and was not measured in this paper.
pressure: pressurised, as stated in the paper
source: arxiv-havar-niobium
where: Abstract and Introduction
risks:
hazards:
- text: Havar-specific SDS not found. The nearest sheet is the ATI family sheet for Cobalt Alloy FRP002, which is a different cobalt alloy (synonyms ATI188, ATIL605 and ATI6230). EU CLP classes it as acute toxicity oral category 4, respiratory sensitisation 1B, skin sensitisation 1, carcinogenicity 1B, reproductive toxicity 2, specific target organ toxicity (repeated exposure) category 1 and chronic aquatic toxicity 4. The sheet says the massive product is an article that does not present a hazard to human health by inhalation or ingestion.
ghs: []
source: ati-cobalt-alloy-sds
where: Section 2.1 classification table and Section 2.2 label elements; Section 2 Other information
- text: 'Cobalt metal, PubChem aggregated GHS data from ECHA notifications (signal word Danger): H317 allergic skin reaction, H334 allergy or asthma symptoms or breathing difficulties if inhaled, H341 suspected of causing genetic defects, H350 may cause cancer, H360F may damage fertility and H413 long-lasting harmful effects to aquatic life. The Havar datasheet gives no classification of its own.'
ghs:
- H317
- H334
- H341
- H350
- H360F
- H413
source: pubchem-cobalt
where: Safety and Hazards, Hazards Identification, GHS Classification (aggregated notifications, cobalt CID 104730)
- text: Welding, burning, melting, sawing, brazing, grinding, buffing and polishing can release hexavalent chromium, which the ATI family sheet says may cause lung, nasal and sinus cancer. Havar contains 19.5 % chromium.
ghs: []
source: ati-cobalt-alloy-sds
where: Section 2, Other Information paragraph on airborne particles and fumes; Section 5.2
failure_risks:
- mode: Low ductility after age hardening
trigger: Bending or forming cold rolled and heat treated strip
consequence: Hamilton prints 1 % elongation in 2 in for the cold rolled and heat treated condition, against 40 % annealed. It asks for forming before age hardening, with a 90 degree bend radius of 8 times the thickness.
severity: moderate
source: hpm-havar-datasheet
where: Typical Mechanical Properties table (elongation row); General Information paragraph
- mode: Attack by boiling strong acids
trigger: Contact with boiling 96 % sulfuric acid or boiling 1 % hydrochloric acid
consequence: Hamilton's 96 h tests give 273.76 mils/year in boiling 96 % sulfuric acid and 237.79 mils/year in boiling 1 % hydrochloric acid. Both are above the 50 mils/year line used for a severe rating in this profile.
severity: critical
source: hpm-havar-corrosion
where: Corrosion Rate table, rows 96% H2SO4 boiling and 1% HCl boiling
- mode: Crevice perforation in seawater
trigger: A crevice in seawater at 86 °F for 720 h
consequence: Hamilton prints perforation at the crevice site for unwelded and welded samples, while the seawater test without a crevice shows no pitting or general attack.
severity: critical
source: hpm-havar-corrosion
where: Second table, rows Seawater and Seawater Crevice Corrosion
- mode: Impurity release from entrance foils in proton beams
trigger: Proton irradiation of enriched water in an F-18 target
consequence: The arXiv paper says bare Havar generates a wide variety of radionuclidic and chemical impurities under this irradiation, which is why coated foils are studied.
severity: moderate
source: arxiv-havar-niobium
where: Introduction
side_effects: []
handling:
- text: Forming cold rolled Havar requires a large radius (90 degree bend, 8 times the thickness) before age hardening.
source: hpm-havar-datasheet
where: General Information paragraph
- text: The ultimate endurance life is achieved by heat treating the alloy at 1000 °F after 80 % cold work, according to Hamilton.
source: hpm-havar-datasheet
where: General Information paragraph
- text: Hamilton says joining can be done by welding and soldering. No welding procedure or weld strength value is given in the sources read.
source: hpm-havar-datasheet
where: General Information paragraph
- text: Fine particles from grinding, buffing or polishing can form combustible dust-air mixtures. Keep them away from heat, sparks and flame, and prevent dust build-up.
source: ati-cobalt-alloy-sds
where: Section 5.2 special hazards and Section 7.1 handling advice
- text: Wear protective gloves and use personal protective equipment as required when handling.
source: ati-cobalt-alloy-sds
where: Section 2.2 precautionary statements
mitigations:
- text: The arXiv paper cites an earlier study in which a sputtered niobium coating on Havar entrance foils cut long-lived ionic impurities by more than ten times.
source: arxiv-havar-niobium
where: Introduction, paragraph on the niobium coating
uses:
- application: mechanisms
device: Power springs
example: Hamilton lists power springs among the applications that have included Havar.
source: hpm-havar-product-page
where: Introduction paragraph (applications list)
- application: propulsion-and-tanks
device: Metal diaphragms for burst discs
example: Hamilton's product page lists metal diaphragms for burst discs and metal diaphragms for aerospace sensors as applications. The page does not name a spacecraft, launch vehicle or tank.
source: hpm-havar-product-page
where: Introduction paragraph (applications list)
- application: electronics-and-chips
device: Gap spacers in magnetic heads
example: Hamilton lists gap spacers in magnetic heads among the applications that have included Havar.
source: hpm-havar-product-page
where: Introduction paragraph (applications list)
- application: radiation-shielding
device: Entrance foil for proton beams in F-18 cyclotron targets
example: The arXiv paper says Havar foils are the entrance foils of targets for F-18 production by proton irradiation of enriched water at pressure. Hamilton also lists target foils in nuclear physics.
source: arxiv-havar-niobium
where: Abstract and Introduction
supply:
- subject: Cobalt (main element, 42.0 % nominal)
producers:
- country: Congo (Kinshasa)
share_percent: 73
year: 2025
- country: Indonesia
share_percent: 14
year: 2025
critical_lists: []
recycling: 'USGS: in 2025, cobalt content of purchased scrap represented 25% of estimated cobalt consumption. USGS also says 51% of cobalt consumed in the United States went into superalloys, mainly for aircraft gas turbine engines.'
substitutes:
- 'USGS: depending on the application, substitution for cobalt could result in a loss in product performance or increased cost.'
- 'USGS: potential substitutes in other applications include nickel-base alloys or ceramics in jet engines.'
source: usgs-mcs2026-cobalt
where: Events, Trends, and Issues (Congo 73 %, Indonesia 14 %); World Mine Production table, 2025e column (Congo 230,000 t, Indonesia 44,000 t, world total 310,000 t); Recycling; Substitutes. The Congo and Indonesia shares are printed in the text.
- subject: Chromium (19.5 % nominal)
producers:
- country: South Africa
share_percent: 45.1
year: 2025
- country: Turkey
share_percent: 17.6
year: 2025
- country: Kazakhstan
share_percent: 13.7
year: 2025
- country: India
share_percent: 5.9
year: 2025
critical_lists: []
recycling: 'USGS: in 2025, recycled chromium in reported stainless-steel scrap receipts accounted for 21% of apparent consumption.'
substitutes:
- 'USGS: chromium has no substitute in stainless steel, the leading end use, or in superalloys, the major strategic end use.'
source: usgs-mcs2026-chromium
where: World Mine Production and Reserves table, 2025e column (South Africa 23,000 t, Turkey 9,000 t, Kazakhstan 7,000 t, India 3,000 t, world total 51,000 t). The shares are calculated by Space Mushroom from those tonnages, since the USGS summary does not print them. Recycling; Substitutes.
documents:
- title: Hamilton Precision Metals (AMETEK), HAVAR technical data sheet, revision V2.12.22
type: datasheet
url: https://www.hpmetals.com/-/media/ametekhpmetals/files/havar.pdf
- title: Hamilton Precision Metals, HAVAR corrosion test data, revision V2.12.22
type: datasheet
url: https://www.hpmetals.com/-/media/ametekhpmetals/files/technical-data/ni-base-corrosion-resistant/havar-corrosion-data.pdf
- title: Hamilton Precision Metals, HAVAR product page (UNS R30004)
type: datasheet
url: https://www.hpmetals.com/products/materials/nickel-strip-foil/havar
- title: Hamilton Precision Metals, HAVAR technical data sheet, Rev. 1 (1/00), archived copy
type: datasheet
url: https://web.archive.org/web/20130510114949/http://www.hpmetals.com/download/Havar.pdf
- title: Skliarova et al., Niobium-based sputtered thin films for corrosion protection of proton-irradiated liquid water targets for [18F] production (arXiv:1308.6605)
type: paper
url: https://arxiv.org/pdf/1308.6605
- title: ATI Cobalt Alloy FRP002 safety data sheet, EU, version 5 (revision 09-Sep-2018)
type: sds
url: https://atimaterials.com/safety-data-sheets/Documents/EuropeanUnion/EU-EN/FRP/FRP002%20Cobalt%20Alloy%20EU-EN%20Rev5.pdf
- title: 'PubChem: Cobalt (CID 104730), GHS classification summary'
type: database
url: https://pubchem.ncbi.nlm.nih.gov/compound/Cobalt
- title: 'USGS Mineral Commodity Summaries 2026: Cobalt'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-cobalt.pdf
- title: 'USGS Mineral Commodity Summaries 2026: Chromium'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
- title: 'Wikipedia: Havar (alloy), composition, history and trade name'
type: database
url: https://en.wikipedia.org/wiki/Havar_(alloy)
gaps:
- No Havar-specific safety data sheet was found. The hazard entries use the ATI family sheet for Cobalt Alloy FRP002, which is a different cobalt alloy with another composition, and the PubChem cobalt summary. Both are labelled as such.
- The ASM Alloy Digest for HAVARAge (Co-24, from Hamilton Precision Metals) is behind a paywall and was not read, so its mechanical, physical and fabrication values are not in this profile.
- Hamilton's technical data sheet gives typical values only and no minimum values. Figure 1 (strength against temperature) is not readable in the PDF text.
- The arXiv paper gives Ni 2.5 %, Fe 19.3 %, W 2.6 % and Mn 1.7 % for Havar, which conflicts with the Hamilton nominal table (Ni 12.7 %, Fe balance, W 2.7 %, Mn 1.6 %). The Hamilton values are used, and the paper's composition is not entered.
- The arXiv paper's tensile value (1860 MPa) and thermal conductivity (14.7 W/(m·K) at 23 °C) differ from the Hamilton values for the cold rolled condition and 13.0 W/(m·K). Both are recorded with their own conditions and not averaged. The Wikipedia tensile range of 960 to 970 MPa matches Hamilton's annealed value of 140,000 psi and is not entered as a property.
- Wikipedia gives a beryllium average of 0.05 wt % (0.02 to 0.08) that is not in the Hamilton nominal composition, so beryllium is not listed as a part of the recipe. Wikipedia's Fe row is internally inconsistent and is not used.
- No melting or manufacturing route (vacuum melting or otherwise) for Havar was stated in the sources read.
- Hamilton's corrosion table gives no rate in mm/year that matches the mils/year printed for boiling 65 % nitric acid (336.30 mils/year against 55 in the mm/year column). That row is left out.
- The Hamilton corrosion table prints the FeCl3 pitting and crevice results for the temperature group, not per temperature, so these results are recorded for the group.
- No ASTM, AMS, EN, DIN or AISI specification number for Havar was printed in any source read in this run. ASTM F-746 and NACE MR0175 are test standards from the corrosion table, not designations, and are not listed as designations.
- The rating for each corrosion entry is an assistant grouping of the printed mils/year (under 5 low, 5 to 50 moderate, over 50 severe), not a rating printed by a source.
- The application tags are the assistant's mapping of Hamilton's device names to the site's application slugs. The burst-disc diaphragms are tagged propulsion-and-tanks and the cyclotron foil radiation-shielding, and the sources do not themselves name those slugs. Hamilton's aerospace-sensor diaphragm use has no matching slug and appears in the text only.
- No flight, spacecraft or launch-vehicle use, and no radiation, outgassing, atomic oxygen or cryogenic data for Havar, was found in any source read in this run.
- Critical-mineral list status for cobalt is not printed in the USGS 2026 cobalt summary text read, so critical_lists is empty. Tungsten and molybdenum supply are not included in this profile (tungsten is 2.7 % and molybdenum 2.2 % of the nominal composition).
- strength_retention, hardness_rockwell_c and the corrosion ratings are short or assistant-chosen names because they are not in the canonical property list, or are not properties at all.
- No image with a checked licence was opened, so the profile has no media entry.
sources:
hpm-havar-datasheet:
title: Hamilton Precision Metals (AMETEK Specialty Metal Products), HAVAR technical data sheet, UNS R30004
id: revision V2.12.22, printed on the sheet
url: https://www.hpmetals.com/-/media/ametekhpmetals/files/havar.pdf
kind: datasheet
license: Manufacturer technical data sheet, typical values for guidance only (cited, not reproduced)
hpm-havar-corrosion:
title: Hamilton Precision Metals, HAVAR corrosion test data (heat 305992, 0.045 in strand annealed strip)
id: revision V2.12.22, printed on the sheet
url: https://www.hpmetals.com/-/media/ametekhpmetals/files/technical-data/ni-base-corrosion-resistant/havar-corrosion-data.pdf
kind: datasheet
license: Manufacturer test data, for guidance only (cited, not reproduced)
hpm-havar-product-page:
title: Hamilton Precision Metals, HAVAR product page (UNS R30004)
url: https://www.hpmetals.com/products/materials/nickel-strip-foil/havar
kind: web
license: Manufacturer web page (cited, not reproduced)
arxiv-havar-niobium:
title: Skliarova et al., Niobium-based sputtered thin films for corrosion protection of proton-irradiated liquid water targets for [18F] production (arXiv:1308.6605)
url: https://arxiv.org/pdf/1308.6605
kind: paper
license: arXiv preprint (cited, not reproduced)
ati-cobalt-alloy-sds:
title: ATI, Safety Data Sheet, Cobalt Alloy FRP002 (EU, English), version 5
id: issue 28-May-2015, revision 09-Sep-2018; a family sheet for a different cobalt alloy
url: https://atimaterials.com/safety-data-sheets/Documents/EuropeanUnion/EU-EN/FRP/FRP002%20Cobalt%20Alloy%20EU-EN%20Rev5.pdf
kind: datasheet
license: Manufacturer safety data sheet (cited, not reproduced)
pubchem-cobalt:
title: PubChem, Cobalt (CID 104730), GHS classification (aggregated ECHA notifications)
url: https://pubchem.ncbi.nlm.nih.gov/compound/Cobalt
kind: database
license: PubChem, public domain (cited, not reproduced)
usgs-mcs2026-cobalt:
title: 'Mineral Commodity Summaries 2026: Cobalt (U.S. Geological Survey, February 2026)'
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-cobalt.pdf
year: 2026
kind: report
license: public domain (USGS)
usgs-mcs2026-chromium:
title: 'Mineral Commodity Summaries 2026: Chromium (U.S. Geological Survey)'
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
year: 2026
kind: report
license: public domain (USGS)
wiki-havar-alloy:
title: Havar (alloy), Wikipedia
url: https://en.wikipedia.org/wiki/Havar_(alloy)
kind: web
license: CC BY-SA (cited, not reproduced); used for the former name Dynavar and history only
license: CC-BY-4.0
updated: '2026-10-26'
review:
status: draft
method: assistant
checked_values: 21
unreachable: 1
caveats: 4
note: 'Values were read by an AI assistant on 2026-10-26 from the Hamilton datasheet and corrosion PDF (V2.12.22), the Hamilton product page, the arXiv paper 1308.6605, the ATI FRP002 sheet, PubChem and USGS MCS 2026. The Havar ASM Alloy Digest (paywalled) was not read. Caveats: the paper''s composition and conductivity/tensile values differ from Hamilton; the hazard sheet is a family sheet for a different cobalt alloy; the corrosion ratings are assistant groupings; the Hamilton FeCl3 results are for temperature groups.'
story:
recipe:
line: Havar is a cobalt-base alloy of cobalt, chromium, nickel, tungsten, molybdenum, manganese and carbon, with iron as the balance (Hamilton nominal composition, wt %). The sources read here do not describe how the alloy is melted or how the strip is made.
parts:
- name: Cobalt
symbol: Co
share_percent: 42
role: Main element. Hamilton calls Havar a cobalt-base alloy.
- name: Chromium
symbol: Cr
share_percent: 19.5
role: Major alloying element. The sources give it no separate role.
- name: Nickel
symbol: Ni
share_percent: 12.7
role: Alloying element. The sources give it no separate role.
- name: Tungsten
symbol: W
share_percent: 2.7
role: Alloying element. The sources give it no separate role.
- name: Molybdenum
symbol: Mo
share_percent: 2.2
role: Alloying element. The sources give it no separate role.
- name: Manganese
symbol: Mn
share_percent: 1.6
role: Alloying element. The sources give it no separate role.
- name: Carbon
symbol: C
share_percent: 0.2
role: Minor element, limited in the nominal composition.
- name: Iron
symbol: Fe
role: Balance element. Hamilton gives iron as the balance, so no share is printed.
risk_groups:
- title: For people
lead: The hazards in the sources come mainly from dust, fume and skin contact during processing. Cobalt is a sensitiser, and welding or grinding can release chromium VI.
level: 1
verdict: Mostly a processing hazard
points:
- label: Solid product
line: The ATI family sheet for cobalt alloy FRP002 says the product is an article that does not present a hazard to health by inhalation or ingestion, but it still lists classes such as carcinogenicity category 1B and skin sensitisation category 1.
- label: Dust and fume
line: Welding, grinding, buffing and polishing can release hexavalent chromium, which the ATI sheet says may cause lung, nasal and sinus cancer. Fine particles can also form combustible dust.
- label: Sensitisation
line: PubChem's aggregated cobalt data lists H317 and H334, which mean an allergic skin reaction and allergy or breathing difficulties if inhaled. The Havar datasheet gives no classification of its own.
- title: If it fails
lead: The failure routes in the sources are about forming, strong acids, crevices and proton-beam impurities. The sources report no measured service failure in space.
points:
- label: Low ductility
line: The cold rolled and heat treated strip elongates 1 % in 2 in, so bends are made before age hardening, with a radius of 8 times the thickness.
- label: Acid attack
line: Boiling 96 % sulfuric acid gives 273.76 mils per year in Hamilton's 96 h test, and boiling 1 % hydrochloric acid gives 237.79 mils per year.
- label: Crevices
line: Hamilton's seawater test shows no pitting or general attack after 720 h at 86 °F, but the crevice test perforates at the crevice site.
- label: Impurities
line: According to the arXiv paper, bare Havar entrance foils release radionuclidic and chemical impurities in proton-irradiated water.
- title: Handling and storage
points:
- label: Forming
line: Bend cold rolled Havar with a 90 degree radius of 8 times the thickness before age hardening.
- label: Heat treatment
line: Heat treating at 1000 °F after 80 % cold work gives the ultimate endurance life, according to Hamilton.
- label: Dust control
line: Keep fine dust from grinding and polishing away from ignition sources, and prevent dust build-up.
why: Havar is a cobalt-base alloy that Hamilton Precision Metals says combines very high strength with excellent corrosion resistance and non-magnetic behaviour. Its cold rolled and heat treated strip reaches 330,000 psi tensile and 300,000 psi yield. Hamilton lists power springs, metal diaphragms for sensors and burst discs, magnetic-head gap spacers and nuclear-physics target foils among its uses, and the arXiv paper describes its use as the entrance foil of F-18 cyclotron targets. The sources read here give no spacecraft flight record.
uses:
- where: Mechanical springs
line: Hamilton lists power springs among the applications that have included Havar.
- where: Diaphragms and burst discs
line: Hamilton lists metal diaphragms for aerospace sensors and for burst discs.
- where: Magnetic heads
line: Hamilton lists gap spacers in magnetic heads.
- where: F-18 cyclotron target window
line: The arXiv paper describes Havar foils as the entrance window for proton beams into enriched water for F-18 production.
can_do:
- label: Strength when cold rolled and heat treated
value: 330,000 psi tensile
benchmark: ultimate_tensile_strength
line: Cold rolled and heat treated Havar gives 330,000 psi tensile and 300,000 psi yield strength, as typical values in the Hamilton datasheet.
- label: Stiffness
value: 29.5 x 10^6 psi
benchmark: elastic_modulus
line: The modulus of elasticity in tension is 29.5 x 10^6 psi, as printed in the Hamilton datasheet.
- label: Strength kept at 950 °F
value: 75 % of room temperature strength
benchmark: strength_retention
line: Hamilton says the alloy retains 75 % of its room temperature strength up to 950 °F.
compare: In Hamilton's 96 h test in boiling 10 % sulfuric acid, Havar corrodes at 9.79 mils per year, against 850 - 2400 for 316L and 20 - 30 for C-276 printed in the same row. In boiling 1 % hydrochloric acid, Havar corrodes at 237.79 mils per year, against 0.2 - 2 for C-276. The comparison rows below use density, thermal conductivity and thermal expansion from the other profiles. The tests differ in form and condition, so read them as examples, not a ranking.
compare_rows:
- label: Density
benchmark: density
- label: Thermal conductivity
benchmark: thermal_conductivity
- label: Thermal expansion
benchmark: cte
handling:
- Bend cold rolled Havar with a radius of 8 times the thickness before age hardening, and heat treat at 1000 °F after 80 % cold work for the endurance life.
- Joining by welding or soldering is possible. No weld procedure or weld strength was found in the sources read.
- Control dust and fine particles from grinding and polishing, and keep them away from ignition sources.
good_for:
- 'Springs and diaphragms: 330,000 psi tensile strength in the cold rolled and heat treated condition, as Hamilton''s typical value.'
- 'Non-magnetic parts: Hamilton lists magnetic attraction as none.'
- 'Seawater: Hamilton''s test shows no pitting or general attack after 720 h at 86 °F.'
watch_out:
- 'Ductility: the cold rolled and heat treated strip elongates 1 % in 2 in.'
- 'Strong boiling acids: 96 % sulfuric acid gives 273.76 mils per year in Hamilton''s test.'
- Welding and grinding fumes can contain hexavalent chromium, according to the ATI sheet for a related cobalt alloy.
- No Havar-specific SDS, no flight record and no ASTM, AMS or EN specification number were found in this run.
verdict: Havar is a strong, non-magnetic cobalt-base alloy, and Hamilton's datasheet and corrosion tests support its use in springs, diaphragms and thin foils. Its ductility after age hardening is low, and boiling strong acids attack it hard. The sources read here show no spacecraft flight record.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
| # | Source | Type | Year | Used for |
|---|---|---|---|---|
| Hamilton Precision Metals (AMETEK Specialty Metal Products), HAVAR technical data sheet, UNS R30004 | datasheet | 24 values | ||
| Hamilton Precision Metals, HAVAR corrosion test data (heat 305992, 0.045 in strand annealed strip) | datasheet | 16 values | ||
| Hamilton Precision Metals, HAVAR product page (UNS R30004) | web | 3 values | ||
| Skliarova et al., Niobium-based sputtered thin films for corrosion protection of proton-irradiated liquid water targets for [18F] production (arXiv:1308.6605) | paper | 6 values | ||
| ATI, Safety Data Sheet, Cobalt Alloy FRP002 (EU, English), version 5 | datasheet | 4 values | ||
| PubChem, Cobalt (CID 104730), GHS classification (aggregated ECHA notifications) | database | 1 value | ||
| Mineral Commodity Summaries 2026: Cobalt (U.S. Geological Survey, February 2026) | report | 2026 | 1 value | |
| Mineral Commodity Summaries 2026: Chromium (U.S. Geological Survey) | report | 2026 | 1 value | |
| Havar (alloy), Wikipedia | web | 0 values |