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.