Electroless nickel-phosphorus plating (AMS 2404 / ASTM B733) NiP
Ni-P alloy deposit, nickel with 1 to 13 % phosphorus by weight (low, medium and high phosphorus grades)
Electroless nickel-phosphorus (NiP) is a nickel coating that contains 1 to 13 % phosphorus by weight, with the grade set by the phosphorus content.
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.
Hardness
200 HV
Hardness after bake
Rc 66 to 70
Service temperature
538 °C
Thermal expansion
13 ppm/K
Recipe, share of the weight
- Ni not statedNickel
- P not statedPhosphorus
Best for
Hard, wear- and corrosion-resistant plating on aluminium connector shells and flight hardware, where a plated finish is specified (NASA recommends it for connector shells)
Weakest at
No space-environment test result (outgassing, atomic oxygen or thermal vacuum) and no measured corrosion rate was found, and the supplier sources disagree on thermal conductivity by about a factor of ten
Risk at a glance
- People No data. No hazard data recorded
- If it fails High. Hydrogen embrittlement of high-strength steel
- Corrosion Low. NASA says the higher-phosphorus deposit gives increased corrosion resistance, and the Kanigen text claims up to five times the corrosion resistance of electrolytic nickel.
Quick facts: NiP
| Property | Value | Basis |
|---|---|---|
| Density | 7.6 to 8.8 g/cm³ | 1 sourced value |
| Thermal conductivity | 4.2 to 70 W/(m·K) | 2 sourced values across conditions |
| Thermal expansion (CTE) | 13 ppm/K | 1 sourced value |
| Melting point | 875 to 1,300 °C | 4 sourced values across conditions |
| Electrical resistivity | 6.8e-8 to 0.0000011 Ω·m | 5 sourced values across conditions |
| Maximum service temperature | 538 °C | 1 sourced value |
What is the density of Electroless nickel-phosphorus plating (NiP)?
Electroless nickel-phosphorus plating (NiP) has a density of 7.6 to 8.8 g/cm³. The source and test conditions are listed in the properties table on this page.
What is the thermal conductivity of Electroless nickel-phosphorus plating (NiP)?
Electroless nickel-phosphorus plating (NiP) has a thermal conductivity of 4.2 to 70 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 Electroless nickel-phosphorus plating (NiP)?
Electroless nickel-phosphorus plating (NiP) has a coefficient of thermal expansion of 13 ppm/K. The source and test conditions are listed in the properties table on this page.
What is the melting point of Electroless nickel-phosphorus plating (NiP)?
Electroless nickel-phosphorus plating (NiP) has a melting point of 875 to 1,300 °C. The range covers 4 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 maximum service temperature of Electroless nickel-phosphorus plating (NiP)?
Electroless nickel-phosphorus plating (NiP) has a maximum service temperature of 538 °C. The source and test conditions are listed in the properties table on this page.
What is Electroless nickel-phosphorus plating (NiP) used for?
Uses recorded in the sources include Aluminium connector shells for space-flight connectors; NASA/JSC flight hardware in steels, aluminium, copper, nickel and cobalt alloys; General wear and corrosion parts.
Why it exists
Electroless nickel-phosphorus (NiP) is a nickel coating used on aluminium and other metals to add hardness, wear resistance and corrosion resistance. The phosphorus content sets the grade, and the grade changes the hardness, melting point and electrical resistivity. NASA's JSC process specification PRC-5007, which applies AMS 2404, is the flight-hardware route, and the medium grade (5 to 9 % P) is the one NASA calls the most widely used for general wear and corrosion resistance.
Where it's used
Space connectors
NASA recommends electroless nickel or gold plating on connector shells. Glenair, which makes space-grade connectors, describes that guidance and lists electroless nickel as the shell finish for its aluminium connectors.
NASA flight hardware
NASA/JSC PRC-5007 governs electroless nickel on steels, stainless steels, aluminium, copper, nickel and cobalt alloys. Its example callout is 0.0010-0.0012 inch on 6061-T6 or 7075-T73 aluminium, Class 4.
Optical mirrors (not established)
Optical aluminium mirrors are the open question. A US patent argues that the nickel layer makes the mirror bimetallic and degrades its figure, and that bare heat-treated aluminium works better. That is the inventors' claim, and no test result we opened supports or refutes it.
Recipe
Ni-P alloy deposit, nickel with 1 to 13 % phosphorus by weight (low, medium and high phosphorus grades)
Electroless nickel-phosphorus is a nickel coating that contains phosphorus, which sets its grade. The grades are low (1 to 4 % P), medium (5 to 9 % P) and high (more than 10 % P) in the Kanigen table, and NASA gives 9 to 13 % P as the higher-corrosion-resistance range.
| Ingredient | Share of the weight | What it does |
|---|---|---|
| Nickel Ni | not stated | The main metal. The coating is nickel with phosphorus dissolved or combined in it, and the nickel sets most of the base metal behaviour. |
| Phosphorus P | not stated | Sets the grade. The phosphorus content changes the hardness, melting point, electrical resistivity and corrosion resistance (see properties). |
Weight shares are as printed in the sources.
What it can do
Hardness
200 HV
measured
As plated, the Kanigen table gives about 520 HV 0.1 for the high-phosphorus grade, about 580 HV 0.1 for the medium grade and about 650 HV for the low grade. After a 290 °C heat treatment for 5 hours it gives about 900 HV 0.1 for the grades.
Hardness after bake
Rc 66 to 70
measured
For the medium grade, the supplier page gives Rc 58 to 62 as plated and Rc 66 to 70 after heat treatment.
Service temperature
538 °C
measured
A finishing reference page states that the AMS 2404C deposit is for service up to 1000F (538 °C).
Thermal expansion
13 ppm/K
measured
The Kanigen table gives a coefficient of thermal expansion of 13 ppm/K at room temperature, the same value for all three grades.
How it compares
Against electrolytic nickel, the Kanigen table gives a medium-phosphorus deposit with higher electrical resistivity (72 µΩ·cm against 6.8 µΩ·cm for electrolytic nickel) and much higher as-plated hardness (about 580 HV 0.1 against 200 HV). The three electroless grades melt between 875 and 910 °C in the same table. The table compares these grades with electrolytic nickel, and the values are the manufacturer's, not a standard.
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.
| Measurement | NiP |
|---|---|
| Thermal behavior and safety | |
| Melting point, KANIGEN MP (medium phosphorus) | 890 °C1 |
| Melting point, KANIGEN HP (high phosphorus) | 875 °C2 |
| Melting point, KANIGEN LP (low phosphorus) | 910 °C3 |
| Melting range, electroless nickel (supplier technical data panel)Range printed in a supplier technical data panel | 890 to 1300 °C4 |
| Thermal conductivity, KANIGEN MP | 0.7 W/(cm·K)6 |
| Thermal conductivity, electroless nickel (supplier technical data panel)Range printed in a supplier technical data panel | 0.042 to 0.067 W/(cm·K) |
| Physical and electrical | |
| Electrical resistivity, KANIGEN HPValue printed in a manufacturer comparison table | 110 µΩ·cm |
| Electrical resistivity, KANIGEN MPValue printed in a manufacturer comparison table | 72 µΩ·cm |
| Electrical resistivity, KANIGEN LPValue printed in a manufacturer comparison table | 30 µΩ·cm |
| Electrical resistivity, electrolytic nickel (comparison column)Value printed in a manufacturer comparison table | 6.8 µΩ·cm |
| Electrical resistivity, electroless nickel (supplier technical data panel)Range printed in a supplier technical data panel | 100 to 1100 nΩ·m5 |
| Hardness as plated, electrolytic nickel (comparison column)Value printed in a manufacturer comparison table | 200 HV |
| Density, electroless nickel (supplier technical data panel)Range printed in a supplier technical data panel | 7.6 to 8.8 g/cm³ |
| Hardness as plated, KANIGEN HPValue printed in a manufacturer comparison table | 520 HV |
| Hardness as plated, KANIGEN MPValue printed in a manufacturer comparison table | 580 HV |
| Hardness as plated, KANIGEN LPValue printed in a manufacturer comparison table | 650 HV7 |
| Hardness after heat treatment, KANIGEN (medium grade row, same value printed for HP and LP)Value printed in a manufacturer comparison table | 900 HV |
| Hardness, non-heat-treated deposit (Kanigen text)Range printed in a manufacturer product text | 500 to 550 HV8 |
| Hardness after heat treatment (Kanigen text)Value printed in a manufacturer product text | 1100 HV9 |
| Hardness, medium phosphorus (6 to 9 % P, Type IV), as platedRange printed in a supplier technical data page | 58 to 62 Rc10 |
| Hardness, medium phosphorus (6 to 9 % P, Type IV), with heat treatmentRange printed in a supplier technical data page | 66 to 70 Rc |
| Minimum hardness, ASTM B733 Class 2 heat treatment | > 850 HK10011 |
| Minimum hardness, AMS 2404 Class 2 heat treatment | > 800 HK10012 |
| Electroless nickel thickness on aluminium, minimum to maximum | 0.001 to 0.003 inch14 |
| Other measurements | |
| Coefficient of thermal expansion, KANIGEN HP, MP and LP (same value printed for each)Value printed in a manufacturer comparison table | 13 ppm/K |
| Service temperature, electroless nickel deposit (AMS 2404C statement) | 538 °C13 |
| Phosphorus content, low phosphorus gradeRange printed in a manufacturer comparison table | 1 to 4 % wt |
| Phosphorus content, medium phosphorus gradeRange printed in a manufacturer comparison table | 5 to 9 % wt |
| Phosphorus content, high phosphorus grade | > 10 % wt15 |
Why choose it, and why not
Good for
- Hard wear and corrosion coatings on aluminium: about 580 HV 0.1 as plated and about 900 HV 0.1 after heat treatment in the medium grade, per the Kanigen table.
- Space connector shells, where NASA recommends electroless nickel or gold plating.
Watch out for
- Sources disagree on thermal conductivity by about ten times (0.7 W/(cm·K) against 0.042 to 0.067 W/(cm·K)); both are recorded.
- No measured corrosion rate and no space-environment test result for the deposit were found.
- Hazard data are for elemental nickel, and the nickel sensitiser code H317 applies to the metal.
- A heat treatment above 500 F can change the deposit from amorphous to crystalline.
Electroless nickel-phosphorus is the standard plated finish that NASA specifies for aluminium flight hardware and connector shells. The medium grade gives about 580 HV 0.1 as plated and about 900 HV 0.1 after heat treatment, and the phosphorus grade changes the properties. This profile lacks a measured corrosion result, a space-environment test and a deposit safety data sheet, and the thermal conductivity sources disagree.
Technical details
For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.
Notes
The method, full conditions and any caveat for the numbered rows above.
| # | Measurement | Method | Conditions | Caveat |
|---|---|---|---|---|
| 1 | Melting point, KANIGEN MP (medium phosphorus) | Value printed in a manufacturer comparison table (technical information, ISO 4527 comparison) | grade KANIGEN MP, 5 - 9 % wt. phosphorustable column MP | — |
| 2 | Melting point, KANIGEN HP (high phosphorus) | Value printed in a manufacturer comparison table (technical information, ISO 4527 comparison) | grade KANIGEN HP, more than 10 % wt. phosphorustable column HP | — |
| 3 | Melting point, KANIGEN LP (low phosphorus) | Value printed in a manufacturer comparison table (technical information, ISO 4527 comparison) | grade KANIGEN LP, 1 - 4 % wt. phosphorustable column LP | — |
| 4 | Melting range, electroless nickel (supplier technical data panel) | — | basis generic range in the supplier technical data panel, not tied to one phosphorus grade | Wider than the three Kanigen grade values (875 to 910 °C). The sources disagree and both are recorded. |
| 5 | Electrical resistivity, electroless nickel (supplier technical data panel) | — | basis generic range in the supplier technical data panel, not tied to one phosphorus grade | Printed in nΩ·m; the Kanigen grades read 30 to 110 µΩ·cm. The sources give different ranges and both are recorded. |
| 6 | Thermal conductivity, KANIGEN MP | Approximate value printed in a manufacturer comparison table | grade KANIGEN MPnote on value printed with a tilde as approximate (~ 0.7) | About ten times the supplier panel range below (0.042 to 0.067 W/(cm·K)). The sources disagree and both are recorded. |
| 7 | Hardness as plated, KANIGEN LP | — | grade KANIGEN LP, as plated (row label: without thermal treatment)load not printed for this row | The LP row prints HV without a test load, so the load is not stated. |
| 8 | Hardness, non-heat-treated deposit (Kanigen text) | — | state non-heat-treated, as printed in the Hardness sectionload 0.1 (printed as HV 0.1) | The same page's table gives 520 to 650 HV 0.1 as plated. The two statements are recorded side by side. |
| 9 | Hardness after heat treatment (Kanigen text) | — | treatment one hour at 400 C or 5 hours at 290 C (as printed)load 0.1 (printed as HV 0.1) | The same page's table gives about 900 HV 0.1 after heat treatment. The two values are recorded side by side. |
| 10 | Hardness, medium phosphorus (6 to 9 % P, Type IV), as plated | — | grade medium phosphorus, 6 to 9 % P as printedcondition as plated | The same page writes the medium grade as 6 to 9 % P, while the NASA text and the ASTM summary on the same page write 5 to 9 % P. |
| 11 | Minimum hardness, ASTM B733 Class 2 heat treatment | Minimum value printed in a supplier summary of ASTM B733 | standard ASTM B733 Class 2condition after hardening heat treatment at 260 to 400 °C | The same page gives 800 HK100 as the AMS 2404 Class 2 minimum. Both are recorded. |
| 12 | Minimum hardness, AMS 2404 Class 2 heat treatment | Minimum value printed in a supplier summary of AMS 2404 | standard AMS 2404 Class 2condition after hardening heat treatment | — |
| 13 | Service temperature, electroless nickel deposit (AMS 2404C statement) | Service temperature statement printed on a finishing reference page; not a test result | standard AMS-2404Cunit in source 1000F (printed as up to 1000F (538C)) | — |
| 14 | Electroless nickel thickness on aluminium, minimum to maximum | Requirement printed in NASA's process specification | substrate aluminium alloysstandard NASA/JSC PRC-5007 Rev. E, Table 1 | Pitting and roughness are a process control problem above 0.0030 inch, per the footnote to Table 1. |
| 15 | Phosphorus content, high phosphorus grade | Lower bound printed in a manufacturer comparison table | grade KANIGEN HPprinted as > 10 % wt. Phosphorus | — |
Corrosion and compatibility
What happens when it meets other materials and environments.
| Environment | Concern | What happens |
|---|---|---|
| Periodic salt-spray check of a corrosion test panel (ASTM B117) | not rated | The process specification requires a 48-hour salt-spray check of a periodic test panel, but it prints no result.1 |
| Higher phosphorus deposits (9 to 13 % P) in corrosive service | low | NASA says the higher-phosphorus deposit gives increased corrosion resistance, and the Kanigen text claims up to five times the corrosion resistance of electrolytic nickel.2 |
| # | Environment | Details | Test conditions |
|---|---|---|---|
| 1 | Periodic salt-spray check of a corrosion test panel (ASTM B117) | NASA/JSC PRC-5007 requires a periodic corrosion test panel to be tested for 48 hours in a continuous salt spray test under ASTM B117. The specification states the test duration only, so no corrosion rate or pass result for this deposit is recorded here. | test continuous salt spray, ASTM B117, 48 hoursresult not printed in the source |
| 2 | Higher phosphorus deposits (9 to 13 % P) in corrosive service | NASA's process specification states that a deposit in the range 9 to 13 % P gives increased corrosion resistance. The Kanigen text states that the coating is up to 5 times more resistant to corrosion than electrolytic nickel, according to the Taber index. The Taber index is a wear index, and the page gives no test conditions, so the five-fold figure is recorded as a claim and not verified. | basis qualitative statement in NASA text and a supplier claim; no measured corrosion ratecomparison electrolytic nickel |
Risks and side effects
Hazards to people, what happens when a cell overheats, and how the material is handled and stored.
For people
The hazard data we could open are for elemental nickel. Nickel is a skin sensitiser, and the deposit's own safety data sheet was not read.
- The metal
- PubChem's GHS record for nickel (CID 935) gives H317, may cause an allergic skin reaction, with the signal word Danger in its main entries. Some notifications also carry H350 and H351, cancer codes.
- Process hazards
- The bath chemicals and the bake ovens are not covered by any source we opened, so their hazards are not recorded here.
If it fails
These failure routes come from NASA's process specification and the supplier text. None is a flight result.
- Poor adhesion on aluminium
- NASA says adhesion can be a problem on aluminium alloys, and it asks for a 180-degree bend test to ASTM B571 over a 4T mandrel.
- Hydrogen in high-strength steel
- NASA requires a hydrogen bakeout at 375 F within four hours of plating for the steels in its Table 2.
- Thick deposits
- Above 0.0030 inch, pitting and roughness become a process control problem, according to NASA.
Handling and storage
- Callout
- NASA requires the thickness, the PRC-5007 reference and the AMS 2404 class on the drawing, and the phosphorus content when it is outside 5 to 9 %.
- Substrate
- NASA's PRC-5007 does not cover titanium or beryllium alloys, while the AMS 2404 and ASTM B733 classes list beryllium alloys.
Test details
The original wording and numbers from the sources, for readers who want them.
Failure risks
| Failure | Trigger and consequence |
|---|---|
| Poor adhesion on aluminium alloysmoderate severity | Plating aluminium without the adhesion steps and checks in the specificationNASA says plating adhesion can be a problem with aluminium alloys. It requires a 180-degree bend test to ASTM B571 over a 4T mandrel, and a Class 3 or Class 4 thermal treatment to improve adhesion. |
| Hydrogen embrittlement of high-strength steelhigh severity | Steel at 150 ksi or more, or tempered below 375 F, plated without a hydrogen bakeoutNASA requires a hydrogen bakeout within four hours of plating for the steels listed in its Table 2. The ASTM B733 summary gives Class 3 at 180 to 200 °C for 2 to 4 hours for steel adhesion and hydrogen embrittlement relief. |
| Pitting and roughness in thick depositslow severity | Deposit thicker than 0.0030 inchNASA notes that pitting and roughness become a process control problem above 0.0030 inch. |
Side effects on surrounding parts
| Affects | Effect |
|---|---|
| Hardness and internal structure of the coating | A post-plate bake above 500 F can change the deposit from amorphous to crystalline and greatly raise its hardness, according to the APT page on electroless deposition. |
| Optical figure of aluminium mirrors (the patent's claim) | A US patent on aluminium mirrors argues that a nickel layer on aluminium is theoretically bimetallic and deforms with temperature, which it says degrades optical performance. The patent gives this as the inventors' position and gives no test result for it. |
Handling and storage
- The specification requires the thickness, the PRC-5007 reference and the AMS 2404 class to be called out on the engineering drawing, and the phosphorus content to be called out when it is outside 5 to 9 %.
- Bake listed steels at 375 F within four hours of plating, per NASA's hydrogen bakeout note. The duration printed in the extracted text is not recorded here.
- NASA PRC-5007 does not cover titanium or beryllium alloys, but the AMS 2404 and ASTM B733 classes list beryllium alloys for the Class 3 and Class 5 treatments.
Mitigations
- Match the heat-treatment class to the substrate: AMS 2404 Class 3 at 375 F for nonheat-treatable aluminium and beryllium, and Class 4 at 250 F for heat-treatable aluminium.
Supply and geography
How common the raw materials are and where they come from.
Nickel (mine production)
- Top producers (2025)
- Indonesia 66.7%, Philippines 6.9%, Russia 5.1%, New Caledonia 3.6%, Canada 3.6%
- Critical mineral lists
- US: listed
- Recycling
- USGS: most secondary nickel was recovered as the nickel content of stainless-steel scrap; nickel in alloyed form was recovered from processing nickel-containing waste.
- Substitutes
- USGS: low-nickel, duplex or ultrahigh-chromium stainless steels have been substituted for austenitic grades in construction, and titanium alloys can substitute for nickel or nickel-base alloys in corrosive environments.
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.
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spore: profile
id: electroless-nickel
spore_version: 0.2
family: nickel-phosphorus-coatings
name: Electroless nickel-phosphorus plating (AMS 2404 / ASTM B733)
abbreviation: NiP
role: Corrosion- and wear-resistant metal coating on aluminium and other substrates
category: coatings
type: conductive-coatings
summary: |
Electroless nickel-phosphorus (NiP) is a nickel coating that contains 1 to 13 % phosphorus by weight, with the grade set by the phosphorus content. The medium grade (5 to 9 % P) is the general-purpose wear and corrosion coating in NASA's process specification. As plated, the Kanigen table gives about 580 HV 0.1 for the medium grade, and about 900 HV 0.1 after a 290 degC heat treatment. NASA's JSC specification PRC-5007 requires a minimum thickness of 0.0010 inch on aluminium alloys and a maximum of 0.0030 inch, and it calls for a hydrogen bakeout at 375 F on listed high-strength steels.
best_for: Hard, wear- and corrosion-resistant plating on aluminium connector shells and flight hardware, where a plated finish is specified (NASA recommends it for connector shells)
weakest_at: No space-environment test result (outgassing, atomic oxygen or thermal vacuum) and no measured corrosion rate was found, and the supplier sources disagree on thermal conductivity by about a factor of ten
identity:
formula: Ni-P alloy deposit, nickel with 1 to 13 % phosphorus by weight (low, medium and high phosphorus grades)
source: nasa-prc-5007
where: Section 3.0 Usage, phosphorus callouts (1 - 3 %, 5 - 9 %, 9 - 13 % P)
tags:
environments: []
stresses: []
applications:
- structures
- electronics-and-chips
- mechanisms
properties:
- benchmark: melting_point
label: Melting point, KANIGEN MP (medium phosphorus)
value: 890
unit: °C
scope: material
conditions:
grade: KANIGEN MP, 5 - 9 % wt. phosphorus
table_column: MP
method: Value printed in a manufacturer comparison table (technical information, ISO 4527 comparison)
status: ground
source: kanigen-atela
where: Technical information table, row Melting point, column MP
- benchmark: melting_point
label: Melting point, KANIGEN HP (high phosphorus)
value: 875
unit: °C
scope: material
conditions:
grade: KANIGEN HP, more than 10 % wt. phosphorus
table_column: HP
method: Value printed in a manufacturer comparison table (technical information, ISO 4527 comparison)
status: ground
source: kanigen-atela
where: Technical information table, row Melting point, column HP
- benchmark: melting_point
label: Melting point, KANIGEN LP (low phosphorus)
value: 910
unit: °C
scope: material
conditions:
grade: KANIGEN LP, 1 - 4 % wt. phosphorus
table_column: LP
method: Value printed in a manufacturer comparison table (technical information, ISO 4527 comparison)
status: ground
source: kanigen-atela
where: Technical information table, row Melting point, column LP
- benchmark: melting_point
label: Melting range, electroless nickel (supplier technical data panel)
value: 890
value_high: 1300
bound: range
unit: °C
scope: material
conditions:
basis: generic range in the supplier technical data panel, not tied to one phosphorus grade
method: Range printed in a supplier technical data panel
status: ground
note: Wider than the three Kanigen grade values (875 to 910 °C). The sources disagree and both are recorded.
source: advplating-specs
where: Electroless Nickel Plating, Technical Data Panel, melting point
- benchmark: electrical_resistivity
label: Electrical resistivity, KANIGEN HP
value: 110
unit: µΩ·cm
scope: material
conditions:
grade: KANIGEN HP, more than 10 % wt. phosphorus
unit_in_source: µOcm (printed)
method: Value printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Electrical resistivity, column HP
- benchmark: electrical_resistivity
label: Electrical resistivity, KANIGEN MP
value: 72
unit: µΩ·cm
scope: material
conditions:
grade: KANIGEN MP, 5 - 9 % wt. phosphorus
unit_in_source: µOcm (printed)
method: Value printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Electrical resistivity, column MP
- benchmark: electrical_resistivity
label: Electrical resistivity, KANIGEN LP
value: 30
unit: µΩ·cm
scope: material
conditions:
grade: KANIGEN LP, 1 - 4 % wt. phosphorus
unit_in_source: µOcm (printed)
method: Value printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Electrical resistivity, column LP
- benchmark: electrical_resistivity
label: Electrical resistivity, electrolytic nickel (comparison column)
value: 6.8
unit: µΩ·cm
scope: material
conditions:
material: electrolytic nickel, the comparison column in the Kanigen table
unit_in_source: µOcm (printed)
method: Value printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Electrical resistivity, column Electrolytic nickel
- benchmark: electrical_resistivity
label: Electrical resistivity, electroless nickel (supplier technical data panel)
value: 100
value_high: 1100
bound: range
unit: nΩ·m
scope: material
conditions:
basis: generic range in the supplier technical data panel, not tied to one phosphorus grade
method: Range printed in a supplier technical data panel
status: ground
note: Printed in nΩ·m; the Kanigen grades read 30 to 110 µΩ·cm. The sources give different ranges and both are recorded.
source: advplating-specs
where: Electroless Nickel Plating, Technical Data Panel, electrical resistivity
- benchmark: hardness_vickers
label: Hardness as plated, electrolytic nickel (comparison column)
value: 200
unit: HV
scope: material
conditions:
material: electrolytic nickel, the comparison column in the Kanigen table
load: not printed for this row
method: Value printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Hardness (without Therm line), column Electrolytic nickel
- benchmark: cte
label: Coefficient of thermal expansion, KANIGEN HP, MP and LP (same value printed for each)
value: 13
unit: ppm/K
scope: material
conditions:
temperature: room temperature
unit_in_source: 13 x 10 – 6 / °K (printed)
method: Value printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Expansion coefficient
- benchmark: thermal_conductivity
label: Thermal conductivity, KANIGEN MP
value: 0.7
unit: W/(cm·K)
scope: material
conditions:
grade: KANIGEN MP
note_on_value: printed with a tilde as approximate (~ 0.7)
method: Approximate value printed in a manufacturer comparison table
status: ground
note: About ten times the supplier panel range below (0.042 to 0.067 W/(cm·K)). The sources disagree and both are recorded.
source: kanigen-atela
where: Technical information table, row Thermal conductivity (W/cm x K), column MP
- benchmark: thermal_conductivity
label: Thermal conductivity, electroless nickel (supplier technical data panel)
value: 0.042
value_high: 0.067
bound: range
unit: W/(cm·K)
scope: material
conditions:
basis: generic range in the supplier technical data panel, not tied to one phosphorus grade
method: Range printed in a supplier technical data panel
status: ground
source: advplating-specs
where: Electroless Nickel Plating, Technical Data Panel, thermal conductivity
- benchmark: density
label: Density, electroless nickel (supplier technical data panel)
value: 7.6
value_high: 8.8
bound: range
unit: g/cm3
scope: material
conditions:
basis: generic range in the supplier technical data panel, not tied to one phosphorus grade
method: Range printed in a supplier technical data panel
status: ground
source: advplating-specs
where: Electroless Nickel Plating, Technical Data Panel, density
- benchmark: hardness_vickers
label: Hardness as plated, KANIGEN HP
value: 520
unit: HV
scope: material
conditions:
grade: 'KANIGEN HP, as plated (row label: without thermal treatment)'
load: 0.1 (printed as HV 0.1)
method: Value printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Hardness (without Therm line), column HP
- benchmark: hardness_vickers
label: Hardness as plated, KANIGEN MP
value: 580
unit: HV
scope: material
conditions:
grade: 'KANIGEN MP, as plated (row label: without thermal treatment)'
load: 0.1 (printed as HV 0.1)
method: Value printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Hardness (without Therm line), column MP
- benchmark: hardness_vickers
label: Hardness as plated, KANIGEN LP
value: 650
unit: HV
scope: material
conditions:
grade: 'KANIGEN LP, as plated (row label: without thermal treatment)'
load: not printed for this row
method: Value printed in a manufacturer comparison table
status: ground
note: The LP row prints HV without a test load, so the load is not stated.
source: kanigen-atela
where: Technical information table, row Hardness (without Therm line), column LP
- benchmark: hardness_vickers
label: Hardness after heat treatment, KANIGEN (medium grade row, same value printed for HP and LP)
value: 900
unit: HV
scope: material
conditions:
treatment: 'thermal treatment at 290 °C for 5 hours (row label: with thermal treatment 290 °C 5 h)'
load: 0.1 (printed as HV 0.1)
method: Value printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Hardness (with trait. Therm 290°C 5h)
- benchmark: hardness_vickers
label: Hardness, non-heat-treated deposit (Kanigen text)
value: 500
value_high: 550
bound: range
unit: HV
scope: material
conditions:
state: non-heat-treated, as printed in the Hardness section
load: 0.1 (printed as HV 0.1)
method: Range printed in a manufacturer product text
status: ground
note: The same page's table gives 520 to 650 HV 0.1 as plated. The two statements are recorded side by side.
source: kanigen-atela
where: Hardness section of the Kanigen page
- benchmark: hardness_vickers
label: Hardness after heat treatment (Kanigen text)
value: 1100
unit: HV
scope: material
conditions:
treatment: one hour at 400 C or 5 hours at 290 C (as printed)
load: 0.1 (printed as HV 0.1)
method: Value printed in a manufacturer product text
status: ground
note: The same page's table gives about 900 HV 0.1 after heat treatment. The two values are recorded side by side.
source: kanigen-atela
where: Hardness section of the Kanigen page
- benchmark: hardness_rockwell_c
label: Hardness, medium phosphorus (6 to 9 % P, Type IV), as plated
value: 58
value_high: 62
bound: range
unit: Rc
scope: material
conditions:
grade: medium phosphorus, 6 to 9 % P as printed
condition: as plated
method: Range printed in a supplier technical data page
status: ground
note: The same page writes the medium grade as 6 to 9 % P, while the NASA text and the ASTM summary on the same page write 5 to 9 % P.
source: advplating-specs
where: Electroless Nickel Plating, Deposit Properties, medium phosphorous row
- benchmark: hardness_rockwell_c
label: Hardness, medium phosphorus (6 to 9 % P, Type IV), with heat treatment
value: 66
value_high: 70
bound: range
unit: Rc
scope: material
conditions:
grade: medium phosphorus, 6 to 9 % P as printed
condition: with heat treatment (temperature and time not printed in this row)
method: Range printed in a supplier technical data page
status: ground
source: advplating-specs
where: Electroless Nickel Plating, Deposit Properties, medium phosphorous row
- benchmark: hardness_knoop
label: Minimum hardness, ASTM B733 Class 2 heat treatment
value: 850
bound: lower
unit: HK100
scope: material
conditions:
standard: ASTM B733 Class 2
condition: after hardening heat treatment at 260 to 400 °C
method: Minimum value printed in a supplier summary of ASTM B733
status: ground
note: The same page gives 800 HK100 as the AMS 2404 Class 2 minimum. Both are recorded.
source: advplating-specs
where: ASTM B733 Class 2 entry, Electroless Nickel Plating page
- benchmark: hardness_knoop
label: Minimum hardness, AMS 2404 Class 2 heat treatment
value: 800
bound: lower
unit: HK100
scope: material
conditions:
standard: AMS 2404 Class 2
condition: after hardening heat treatment
method: Minimum value printed in a supplier summary of AMS 2404
status: ground
source: advplating-specs
where: AMS 3.4.4 (Class 2 hardness), Electroless Nickel Plating page
- benchmark: max_service_temp
label: Service temperature, electroless nickel deposit (AMS 2404C statement)
value: 538
unit: °C
scope: material
conditions:
standard: AMS-2404C
unit_in_source: 1000F (printed as up to 1000F (538C))
method: Service temperature statement printed on a finishing reference page; not a test result
status: ground
source: engineersedge
where: Introduction (AMS-2404C, AMS-2505B, AMS-2433B)
- benchmark: coating_thickness
label: Electroless nickel thickness on aluminium, minimum to maximum
value: 0.001
value_high: 0.003
bound: range
unit: inch
scope: material
conditions:
substrate: aluminium alloys
standard: NASA/JSC PRC-5007 Rev. E, Table 1
method: Requirement printed in NASA's process specification
status: ground
note: Pitting and roughness are a process control problem above 0.0030 inch, per the footnote to Table 1.
source: nasa-prc-5007
where: Table 1, Thickness Requirements for Electroless Nickel Plate, row Aluminum
- benchmark: phosphorus_content
label: Phosphorus content, low phosphorus grade
value: 1
value_high: 4
bound: range
unit: '% wt'
scope: material
conditions:
grade: KANIGEN LP
method: Range printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Chemical composition, column LP
- benchmark: phosphorus_content
label: Phosphorus content, medium phosphorus grade
value: 5
value_high: 9
bound: range
unit: '% wt'
scope: material
conditions:
grade: KANIGEN MP
method: Range printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Chemical composition, column MP
- benchmark: phosphorus_content
label: Phosphorus content, high phosphorus grade
value: 10
bound: lower
unit: '% wt'
scope: material
conditions:
grade: KANIGEN HP
printed_as: '> 10 % wt. Phosphorus'
method: Lower bound printed in a manufacturer comparison table
status: ground
source: kanigen-atela
where: Technical information table, row Chemical composition, column HP
corrosion:
- environment: Periodic salt-spray check of a corrosion test panel (ASTM B117)
headline: The process specification requires a 48-hour salt-spray check of a periodic test panel, but it prints no result.
effect: NASA/JSC PRC-5007 requires a periodic corrosion test panel to be tested for 48 hours in a continuous salt spray test under ASTM B117. The specification states the test duration only, so no corrosion rate or pass result for this deposit is recorded here.
rating: unknown
conditions:
test: continuous salt spray, ASTM B117, 48 hours
result: not printed in the source
source: nasa-prc-5007
where: Section 7.0 Process qualification
- environment: Higher phosphorus deposits (9 to 13 % P) in corrosive service
headline: NASA says the higher-phosphorus deposit gives increased corrosion resistance, and the Kanigen text claims up to five times the corrosion resistance of electrolytic nickel.
effect: NASA's process specification states that a deposit in the range 9 to 13 % P gives increased corrosion resistance. The Kanigen text states that the coating is up to 5 times more resistant to corrosion than electrolytic nickel, according to the Taber index. The Taber index is a wear index, and the page gives no test conditions, so the five-fold figure is recorded as a claim and not verified.
rating: low
conditions:
basis: qualitative statement in NASA text and a supplier claim; no measured corrosion rate
comparison: electrolytic nickel
source: nasa-prc-5007
where: Section 3.0 Usage, higher phosphorous coating callout; the five-fold claim is in the Kanigen page text, Wear resistance and Corrosion resistance sections
risks:
hazards:
- text: PubChem's GHS record for nickel (CID 935) gives H317, May cause an allergic skin reaction, with the signal word Danger in its main entries. Some notifications in the same record also carry H350 and H351 cancer codes. The record is for elemental nickel, not for the phosphorus-containing deposit.
ghs:
- H317
source: pubchem-nickel
where: GHS Classification section, aggregated company notifications (CID 935)
failure_risks:
- mode: Poor adhesion on aluminium alloys
trigger: Plating aluminium without the adhesion steps and checks in the specification
consequence: NASA says plating adhesion can be a problem with aluminium alloys. It requires a 180-degree bend test to ASTM B571 over a 4T mandrel, and a Class 3 or Class 4 thermal treatment to improve adhesion.
severity: moderate
source: nasa-prc-5007
where: Section 7.0 Process qualification; Section 3.0 classes
- mode: Hydrogen embrittlement of high-strength steel
trigger: Steel at 150 ksi or more, or tempered below 375 F, plated without a hydrogen bakeout
consequence: NASA requires a hydrogen bakeout within four hours of plating for the steels listed in its Table 2. The ASTM B733 summary gives Class 3 at 180 to 200 °C for 2 to 4 hours for steel adhesion and hydrogen embrittlement relief.
severity: high
source: nasa-prc-5007
where: Table 2 (steels that require a hydrogen bakeout) and the hydrogen bakeout note in Section 3.0
- mode: Pitting and roughness in thick deposits
trigger: Deposit thicker than 0.0030 inch
consequence: NASA notes that pitting and roughness become a process control problem above 0.0030 inch.
severity: low
source: nasa-prc-5007
where: Table 1 footnote
side_effects:
- text: A post-plate bake above 500 F can change the deposit from amorphous to crystalline and greatly raise its hardness, according to the APT page on electroless deposition.
affects: Hardness and internal structure of the coating
source: advplating-specs
where: What is Electroless Deposition section
- text: A US patent on aluminium mirrors argues that a nickel layer on aluminium is theoretically bimetallic and deforms with temperature, which it says degrades optical performance. The patent gives this as the inventors' position and gives no test result for it.
affects: Optical figure of aluminium mirrors (the patent's claim)
source: us6350176
where: Background and summary text of the patent
handling:
- text: The specification requires the thickness, the PRC-5007 reference and the AMS 2404 class to be called out on the engineering drawing, and the phosphorus content to be called out when it is outside 5 to 9 %.
source: nasa-prc-5007
where: Section 3.0 Usage and the phosphorus callout text
- text: Bake listed steels at 375 F within four hours of plating, per NASA's hydrogen bakeout note. The duration printed in the extracted text is not recorded here.
source: nasa-prc-5007
where: Section 3.0 hydrogen bakeout note and Table 2
- text: NASA PRC-5007 does not cover titanium or beryllium alloys, but the AMS 2404 and ASTM B733 classes list beryllium alloys for the Class 3 and Class 5 treatments.
source: nasa-prc-5007
where: Section 2.0 Applicability; the class list is on the Electroless Nickel Plating specifications page (advplating-specs)
mitigations:
- text: 'Match the heat-treatment class to the substrate: AMS 2404 Class 3 at 375 F for nonheat-treatable aluminium and beryllium, and Class 4 at 250 F for heat-treatable aluminium.'
source: advplating-specs
where: AMS 2404 classes, Electroless Nickel Plating specifications page
uses:
- application: electronics-and-chips
device: Aluminium connector shells for space-flight connectors
example: NASA recommends electroless nickel or gold plating on connector shells, and Glenair describes that guidance for its space-grade connectors, which list electroless nickel as the shell finish.
source: glenair-hiper-d
where: Connector Material and Finish for Space Applications panel
- application: structures
device: NASA/JSC flight hardware in steels, aluminium, copper, nickel and cobalt alloys
example: NASA's example callout is electroless nickel plate to a thickness of 0.0010-0.0012 inch per NASA/JSC PRC-5007, Class 4, for a 6061-T6 or 7075-T73 aluminium alloy.
source: nasa-prc-5007
where: Section 3.0 Usage, example callout
- application: mechanisms
device: General wear and corrosion parts
example: NASA states that the medium phosphorus coating (5 - 9 % P) is the most widely used for the general-purpose requirements of wear and corrosion resistance.
source: nasa-prc-5007
where: Section 3.0 Usage, phosphorus callout text
supply:
- subject: Nickel (mine production)
producers:
- country: Indonesia
share_percent: 66.7
year: 2025
- country: Philippines
share_percent: 6.9
year: 2025
- country: Russia
share_percent: 5.1
year: 2025
- country: New Caledonia
share_percent: 3.6
year: 2025
- country: Canada
share_percent: 3.6
year: 2025
critical_lists:
- list: USGS 2025 List of Critical Minerals (printed as Nickel, used to make high-strength steel, and rechargeable batteries)
listed: true
recycling: 'USGS: most secondary nickel was recovered as the nickel content of stainless-steel scrap; nickel in alloyed form was recovered from processing nickel-containing waste.'
substitutes:
- 'USGS: low-nickel, duplex or ultrahigh-chromium stainless steels have been substituted for austenitic grades in construction, and titanium alloys can substitute for nickel or nickel-base alloys in corrosive environments.'
source: usgs-mcs2026-nickel
where: World Mine Production and Reserves table, 2025e (world total 3,900,000 t, rounded; shares calculated by Space Mushroom from the country values 2,600,000; 270,000; 200,000; 140,000; 140,000 t); Recycling; Substitutes; critical list from the USGS 2025 list page
media: []
documents:
- title: NASA/JSC PRC-5007 Rev. E, Process Specification for Electroless Nickel Plating (May 2020)
type: standard
url: https://www.nasa.gov/wp-content/uploads/2023/03/prc-5007-current.pdf
year: 2020
- title: Glenair HiPer-D space-grade connector information, Connector Material and Finish for Space Applications
type: datasheet
url: https://www.glenair.com/hiper-d/pdf/space-grade-hiper-d-information.pdf
year: 2026
- title: 'USGS Mineral Commodity Summaries 2026: Nickel'
type: report
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
year: 2026
- title: PubChem compound record, Nickel (CID 935), GHS classification
type: database
url: https://pubchem.ncbi.nlm.nih.gov/compound/Nickel
year: 2026
- title: Kanigen technical information table (KANIGEN HP, MP, LP and electrolytic nickel)
type: datasheet
url: https://coatings.atela.ch/en/coatings/kanigen-mp/
gaps:
- No measured corrosion rate, salt-spray pass result or ISO 9227 result for the deposit was found in an opened source; the NASA 48-hour salt-spray requirement is recorded as a requirement only.
- No space-environment result for the deposit (outgassing, total mass loss, atomic oxygen, thermal vacuum or cold welding) was found in a source we opened. The space link is NASA's connector guidance and its flight-hardware specification.
- Density values for the Kanigen grades (7.9, 8.2, 8.5 and 8.9) are printed without a unit in the table, so they are not recorded.
- The Kanigen high-phosphorus thermal conductivity is printed as '0.044 – 00.57' (garbled), so it is not recorded.
- The Kanigen Taber wear index values (8, 6, 3 and 14) are printed without a unit, and the page's 'up to 5 times' wear claim does not match its own numbers, so they are not recorded.
- A Knoop microhardness of 500-720 from the APT blog is printed with no unit and no as-plated or heat-treated label, so it is not recorded.
- The Nickel Institute properties PDF (density by phosphorus content, resistivity, melting point) returned HTTP 403 and could not be read; the density and melting ranges here come from supplier pages.
- Process chemistry (how the deposit is reduced without electric current) was not read in a fetched page, so the recipe lists the elements and the phosphorus grades only.
- 'Hydrogen bakeout duration: the NASA text extraction prints ''23 hours'' for the 375 F bake, which looks like a line-break error, so the duration is not recorded.'
- Hazard data rest on the PubChem record for elemental nickel. No supplier safety data sheet for a nickel-phosphorus deposit or its bath chemicals was read, and the PubChem record mixes notifications for several nickel forms.
- Phosphorus supply and nickel-bath chemical supply were not looked up. The EU critical raw materials list status for nickel was not checked.
- 'Optical use: no fetched source gives a test result for electroless nickel on an aluminium optic. The Fraunhofer and ESA optics work seen in search results was not opened, and the patent is recorded only as an inventors'' claim.'
- Sources disagree on several values (thermal conductivity by about ten times, melting range, phosphorus ranges of 5 to 9 % against 6 to 9 %, heat-treated hardness of about 900 against 1100 HV 0.1). Both values are recorded side by side, and none is chosen.
- 'Property names not in spores/property-canon.yaml: hardness_vickers, hardness_knoop, hardness_rockwell_c, coating_thickness and phosphorus_content.'
- 'Beryllium and titanium: NASA PRC-5007 excludes both, while AMS 2404 Class 3 and ASTM B733 cover beryllium. No beryllium deposit value was read.'
sources:
kanigen-atela:
title: KANIGEN technical information table (HP, MP, LP and electrolytic nickel, ISO 4527 comparison), coatings.atela.ch
url: https://coatings.atela.ch/en/coatings/kanigen-mp/
kind: datasheet
license: Manufacturer-derived comparison table (cited, not reproduced)
advplating-blog:
title: Electroless nickel phosphorus content (Advanced Plating Technologies blog)
url: https://advancedplatingtech.com/blog/electroless-nickel-phosphorus-content/
kind: web
license: Supplier web page (cited, not reproduced)
advplating-specs:
title: Electroless Nickel Plating per MIL-C-26074, ASTM B733 and AMS 2404 (Advanced Plating Technologies)
url: https://advancedplatingtech.com/electroless-nickel/electroless-nickel-plating/
kind: web
license: Supplier web page (cited, not reproduced)
engineersedge:
title: Electroless nickel plating (EngineersEdge finishing reference)
url: https://engineersedge.com/finishing/electroless_nickel.htm
kind: web
license: Reference web page (cited, not reproduced)
nasa-prc-5007:
title: NASA/JSC PRC-5007 Rev. E, Process Specification for Electroless Nickel Plating (Engineering Directorate, May 2020)
url: https://www.nasa.gov/wp-content/uploads/2023/03/prc-5007-current.pdf
kind: standard
license: Public domain (NASA)
usgs-mcs2026-nickel:
title: Mineral Commodity Summaries 2026, Nickel
id: USGS MCS 2026, February 2026
url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
kind: report
license: Public domain (USGS)
usgs-crit2025:
title: About the 2025 List of Critical Minerals (USGS, final list of 60 minerals)
url: https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals
kind: web
license: Public domain (USGS)
glenair-hiper-d:
title: Glenair HiPer-D space-grade connector information, Connector Material and Finish for Space Applications
url: https://www.glenair.com/hiper-d/pdf/space-grade-hiper-d-information.pdf
kind: datasheet
license: Manufacturer document (cited, not reproduced)
us6350176:
title: US Patent 6,350,176 B3, High quality optically polished aluminum mirror and process for producing (copy on NTRS 20080005024)
url: https://ntrs.nasa.gov/api/citations/20080005024/downloads/20080005024.pdf
kind: report
license: Patent document (cited, not reproduced)
pubchem-nickel:
title: PubChem compound record, Nickel (CID 935), GHS classification
id: CID 935
url: https://pubchem.ncbi.nlm.nih.gov/compound/Nickel
kind: database
license: PubChem (NCBI), public domain; notifications attributed to ECHA C&L Inventory
license: CC-BY-4.0
updated: '2026-11-01'
review:
status: draft
method: assistant
checked_values: 29
unreachable: 2
caveats: 4
note: 'Values read by an AI assistant on 2026-11-01 from the web pages and PDFs named in each entry. Unreachable: the Nickel Institute properties PDF (HTTP 403) and the PubChem summary page as HTML (browser check); the PubChem JSON record was read through its data API. Caveats: supplier values are not from a standard; the sources disagree on several values; the hazard data are for elemental nickel; the optics use is not supported by a test result.'
story:
recipe:
line: Electroless nickel-phosphorus is a nickel coating that contains phosphorus, which sets its grade. The grades are low (1 to 4 % P), medium (5 to 9 % P) and high (more than 10 % P) in the Kanigen table, and NASA gives 9 to 13 % P as the higher-corrosion-resistance range.
parts:
- name: Nickel
symbol: Ni
share: the balance of the deposit
role: The main metal. The coating is nickel with phosphorus dissolved or combined in it, and the nickel sets most of the base metal behaviour.
- name: Phosphorus
symbol: P
share: 1 to 4 % by weight (low), 5 to 9 % (medium), more than 10 % (high)
role: Sets the grade. The phosphorus content changes the hardness, melting point, electrical resistivity and corrosion resistance (see properties).
risk_groups:
- title: For people
lead: The hazard data we could open are for elemental nickel. Nickel is a skin sensitiser, and the deposit's own safety data sheet was not read.
points:
- label: The metal
line: PubChem's GHS record for nickel (CID 935) gives H317, may cause an allergic skin reaction, with the signal word Danger in its main entries. Some notifications also carry H350 and H351, cancer codes.
- label: Process hazards
line: The bath chemicals and the bake ovens are not covered by any source we opened, so their hazards are not recorded here.
- title: If it fails
lead: These failure routes come from NASA's process specification and the supplier text. None is a flight result.
points:
- label: Poor adhesion on aluminium
line: NASA says adhesion can be a problem on aluminium alloys, and it asks for a 180-degree bend test to ASTM B571 over a 4T mandrel.
- label: Hydrogen in high-strength steel
line: NASA requires a hydrogen bakeout at 375 F within four hours of plating for the steels in its Table 2.
- label: Thick deposits
line: Above 0.0030 inch, pitting and roughness become a process control problem, according to NASA.
- title: Handling and storage
points:
- label: Callout
line: NASA requires the thickness, the PRC-5007 reference and the AMS 2404 class on the drawing, and the phosphorus content when it is outside 5 to 9 %.
- label: Substrate
line: NASA's PRC-5007 does not cover titanium or beryllium alloys, while the AMS 2404 and ASTM B733 classes list beryllium alloys.
why: Electroless nickel-phosphorus (NiP) is a nickel coating used on aluminium and other metals to add hardness, wear resistance and corrosion resistance. The phosphorus content sets the grade, and the grade changes the hardness, melting point and electrical resistivity. NASA's JSC process specification PRC-5007, which applies AMS 2404, is the flight-hardware route, and the medium grade (5 to 9 % P) is the one NASA calls the most widely used for general wear and corrosion resistance.
uses:
- where: Space connectors
line: NASA recommends electroless nickel or gold plating on connector shells. Glenair, which makes space-grade connectors, describes that guidance and lists electroless nickel as the shell finish for its aluminium connectors.
- where: NASA flight hardware
line: NASA/JSC PRC-5007 governs electroless nickel on steels, stainless steels, aluminium, copper, nickel and cobalt alloys. Its example callout is 0.0010-0.0012 inch on 6061-T6 or 7075-T73 aluminium, Class 4.
- where: Optical mirrors (not established)
line: Optical aluminium mirrors are the open question. A US patent argues that the nickel layer makes the mirror bimetallic and degrades its figure, and that bare heat-treated aluminium works better. That is the inventors' claim, and no test result we opened supports or refutes it.
can_do:
- label: Hardness
benchmark: hardness_vickers
line: As plated, the Kanigen table gives about 520 HV 0.1 for the high-phosphorus grade, about 580 HV 0.1 for the medium grade and about 650 HV for the low grade. After a 290 °C heat treatment for 5 hours it gives about 900 HV 0.1 for the grades.
- label: Hardness after bake
benchmark: hardness_rockwell_c
value: Rc 66 to 70
line: For the medium grade, the supplier page gives Rc 58 to 62 as plated and Rc 66 to 70 after heat treatment.
- label: Service temperature
benchmark: max_service_temp
value: 538 °C
line: A finishing reference page states that the AMS 2404C deposit is for service up to 1000F (538 °C).
- label: Thermal expansion
benchmark: cte
value: 13 ppm/K
line: The Kanigen table gives a coefficient of thermal expansion of 13 ppm/K at room temperature, the same value for all three grades.
compare: Against electrolytic nickel, the Kanigen table gives a medium-phosphorus deposit with higher electrical resistivity (72 µΩ·cm against 6.8 µΩ·cm for electrolytic nickel) and much higher as-plated hardness (about 580 HV 0.1 against 200 HV). The three electroless grades melt between 875 and 910 °C in the same table. The table compares these grades with electrolytic nickel, and the values are the manufacturer's, not a standard.
compare_rows:
- label: Hardness as plated (medium grade)
benchmark: hardness_vickers
- label: Electrical resistivity (medium grade)
benchmark: electrical_resistivity
- label: Thermal expansion
benchmark: cte
handling:
- Call out the thickness, the PRC-5007 reference and the AMS 2404 class on the drawing.
- Bake listed high-strength steels at 375 F within four hours of plating.
- Keep the phosphorus grade on the drawing, because hardness and resistivity change with it.
- Do not plate titanium or beryllium under PRC-5007 without checking the AMS or ASTM class for beryllium.
good_for:
- 'Hard wear and corrosion coatings on aluminium: about 580 HV 0.1 as plated and about 900 HV 0.1 after heat treatment in the medium grade, per the Kanigen table.'
- Space connector shells, where NASA recommends electroless nickel or gold plating.
watch_out:
- Sources disagree on thermal conductivity by about ten times (0.7 W/(cm·K) against 0.042 to 0.067 W/(cm·K)); both are recorded.
- No measured corrosion rate and no space-environment test result for the deposit were found.
- Hazard data are for elemental nickel, and the nickel sensitiser code H317 applies to the metal.
- A heat treatment above 500 F can change the deposit from amorphous to crystalline.
verdict: Electroless nickel-phosphorus is the standard plated finish that NASA specifies for aluminium flight hardware and connector shells. The medium grade gives about 580 HV 0.1 as plated and about 900 HV 0.1 after heat treatment, and the phosphorus grade changes the properties. This profile lacks a measured corrosion result, a space-environment test and a deposit safety data sheet, and the thermal conductivity sources disagree.
References
Every number above carries a reference number. Click one to see the source and where in it the value comes from.
Updated