Cobalt-chromium-molybdenum ASTM F75 (CoCrMo) CoCrMo

spore: profile
id: cobalt-chromium-f75
spore_version: 0.2
family: cobalt-alloys
name: Cobalt-chromium-molybdenum ASTM F75 (CoCrMo)
abbreviation: CoCrMo
role: cobalt-base casting alloy for surgical implants, also sold as a powder for additive manufacturing
category: metals
type: nickel-superalloys
summary: |
  ASTM F75 (UNS R30075, ISO 5832-4) is a cobalt-chromium-molybdenum alloy written as Co-28Cr-6Mo, with 27.0 to 30.0 wt% chromium and 5.0 to 7.0 wt% molybdenum. It is specified as a casting alloy for surgical implants. ICAST gives a minimum tensile strength of 655 MPa and a minimum yield strength of 450 MPa for the cast grade. VDM sells a spherical powder of the same composition for additive manufacturing, with a density of 8.3 g/cm3 at 20 °C.
best_for: Wear- and corrosion-resistant metal parts that must stay strong at high temperature, such as implant parts and gas-turbine nozzles and vanes (VDM)
weakest_at: Only minimum strengths are given for the cast grade (ICAST); no cast-grade modulus, thermal conductivity or hot-strength value was found, and the additive values come from one datasheet
identity:
  formula: 'Co-28Cr-6Mo cobalt-base alloy. ASTM F75 composition limits in wt% (VDM Table 2): Co balance; Cr 27.0 to 30.0; Mo 5.0 to 7.0; Ni 0.50 max; Fe 0.75 max; C 0.35 max; Si 1.0 max; Mn 1.0 max; W 0.20 max; P 0.020 max; S 0.010 max; N 0.25 max; Al 0.10 max; Ti 0.10 max; B 0.010 max'
  source: vdm-f75
  where: Table 2, Chemical composition (%) according to ASTM F75 (VDM data sheet No. 2006); the ICAST composition table gives the same limits
  designations:
    - system: UNS
      code: R30075
      source: icast-f75
      where: Title block (Material ASTM F 75 R30075) and Cross Reference Table, row R30075 (UNS, USA)
    - system: ASTM
      code: F75
      source: icast-f75
      where: 'Title block: Standard Specification for Cobalt-28 Chromium-6 Molybdenum Casting Alloy and Cast Products for Surgical Implants'
    - system: ISO
      code: 5832-4
      source: vdm-f75
      where: Table 1 Designations, ISO row (5832-12 / 5832-4)
    - system: ASTM
      code: F1537
      note: wrought bar and billet standard; VDM lists it with F75 against its powder
      source: vdm-f75
      where: Table 1 Designations, ASTM row (F1537-11 / F75)
    - system: JIS
      code: 7402-1
      source: icast-f75
      where: Cross Reference Table, row 7402-1 (JIS, Japan)
tags:
  environments: []
  stresses: []
  applications:
    - in-space-manufacturing
    - propulsion-and-tanks
    - structures
properties:
  - benchmark: density
    label: Density, CoCr F75 powder for additive manufacturing
    value: 8.3
    unit: g/cm3
    scope: material
    conditions:
      form: spherical powder, VDM Powder CoCr F75
      temperature: 20 °C (68 °F)
      unit_in_source: 8.3 g/cm3 at 20 °C (68 °F)
    method: Value printed in a producer's material data sheet
    status: ground
    source: vdm-f75
    where: Physical properties, Density
  - benchmark: melting_point
    label: Melting range, CoCr F75 powder
    value: 1350
    value_high: 1430
    bound: range
    unit: °C
    scope: material
    conditions:
      form: VDM Powder CoCr F75
      unit_in_source: 1,350-1,430 °C (2,462-2,606 °F)
    method: Melting range printed in a producer's material data sheet
    status: ground
    source: vdm-f75
    where: Physical properties, Melting range
  - benchmark: oxygen_content
    label: Oxygen content of CoCr F75 powder, upper limit
    value: 0.03
    bound: upper
    unit: '%'
    scope: material
    conditions:
      form: VDM Powder CoCr F75 spherical powder
      unit_in_source: up to 0.03 %
      basis: maximum, printed as up to
    method: Maximum printed in a producer's material data sheet
    status: ground
    note: oxygen_content is not a canonical name in spores/property-canon.yaml; this snake_case name was chosen for the row.
    source: vdm-f75
    where: Chemical composition text (low amounts of oxygen of up to 0.03 %) and Standard particle fractions table (oxygen content < 0.03 %)
  - benchmark: yield_strength
    label: Yield strength, cast ASTM F75 minimum
    value: 450
    bound: lower
    unit: MPa
    scope: material
    conditions:
      grade: ASTM F75 R30075 cast
      heat_treatment: As-Cast or Annealing (the sheet does not separate them)
      basis: minimum as printed
    method: Minimum value printed in a casting producer's data sheet
    status: ground
    source: icast-f75
    where: Mechanical Properties box, Yield Strength in Mpa 450 min.
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, cast ASTM F75 minimum
    value: 655
    bound: lower
    unit: MPa
    scope: material
    conditions:
      grade: ASTM F75 R30075 cast
      heat_treatment: As-Cast or Annealing (the sheet does not separate them)
      basis: minimum as printed
    method: Minimum value printed in a casting producer's data sheet
    status: ground
    source: icast-f75
    where: Mechanical Properties box, Tensile Strength in Mpa 655 min.
  - benchmark: elongation
    label: Elongation, cast ASTM F75 minimum
    value: 8
    bound: lower
    unit: '%'
    scope: material
    conditions:
      grade: ASTM F75 R30075 cast
      basis: minimum as printed, gauge length not stated
    method: Minimum value printed in a casting producer's data sheet
    status: ground
    source: icast-f75
    where: Mechanical Properties box, Elongation in % 8 min.
  - benchmark: hardness_rockwell_c
    label: Hardness, cast ASTM F75 range
    value: 25
    value_high: 35
    bound: range
    unit: HRC
    scope: material
    conditions:
      grade: ASTM F75 R30075 cast
      heat_treatment: As-Cast or Annealing (the sheet does not separate them)
    method: Range printed in a casting producer's data sheet
    status: ground
    note: hardness_rockwell_c is not a canonical name in spores/property-canon.yaml; this snake_case name was chosen for the row.
    source: icast-f75
    where: Mechanical Properties box, Hardness in HRC 25 - 35
  - benchmark: elastic_modulus
    label: Young's modulus, laser-sintered LaserForm CoCrF75 (A), after anneal
    value: 225
    unit: GPa
    scope: material
    conditions:
      form: additive, laser-sintered on ProX DMP 320 (not cast), after anneal
      test: ASTM E8M
      tolerance: 225 ± 5 GPa as printed
    method: Value printed in a manufacturer datasheet for its additive material
    status: ground
    source: 3dsystems-cocrf75
    where: Mechanical Properties table, Youngs modulus row, column AFTER ANNEAL
  - benchmark: yield_strength
    label: Yield strength Rp0.2, laser-sintered LaserForm CoCrF75 (A), horizontal, after anneal
    value: 540
    unit: MPa
    scope: material
    conditions:
      form: additive, laser-sintered on ProX DMP 320 (not cast), horizontal direction XY, after anneal
      test: ASTM E8M
      tolerance: 540 ± 30 MPa as printed
    method: Value printed in a manufacturer datasheet for its additive material
    status: ground
    note: The vertical build direction (Z) gives 520 ± 30 MPa in the same table, so build direction changes the value.
    source: 3dsystems-cocrf75
    where: Mechanical Properties table, Yield strength Rp0.2% row, Horizontal direction XY, AFTER ANNEAL
  - benchmark: ultimate_tensile_strength
    label: Ultimate strength, laser-sintered LaserForm CoCrF75 (A), horizontal, after anneal
    value: 1030
    unit: MPa
    scope: material
    conditions:
      form: additive, laser-sintered on ProX DMP 320 (not cast), horizontal direction XY, after anneal
      test: ASTM E8M
      tolerance: 1030 ± 70 MPa as printed
    method: Value printed in a manufacturer datasheet for its additive material
    status: ground
    source: 3dsystems-cocrf75
    where: Mechanical Properties table, Ultimate strength row, Horizontal direction XY, AFTER ANNEAL
  - benchmark: elongation
    label: Elongation at break, laser-sintered LaserForm CoCrF75 (A), horizontal, after anneal
    value: 29
    unit: '%'
    scope: material
    conditions:
      form: additive, laser-sintered on ProX DMP 320 (not cast), horizontal direction XY, after anneal
      test: ASTM E8M
      tolerance: 29 ± 6 % as printed
    method: Value printed in a manufacturer datasheet for its additive material
    status: ground
    source: 3dsystems-cocrf75
    where: Mechanical Properties table, Elongation at break row, Horizontal direction XY, AFTER ANNEAL
  - benchmark: density
    label: Absolute theoretical density, LaserForm CoCrF75 (A)
    value: 8.35
    unit: g/cm3
    scope: material
    conditions:
      basis: absolute theoretical density; the datasheet's footnote 5 says values are based on literature
      unit_in_source: 8.35 g/cm³
    method: Theoretical density printed in a manufacturer datasheet, which marks it as based on literature
    status: ground
    source: 3dsystems-cocrf75
    where: Physical Properties table, Density, Absolute theoretical row
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 20 °C, LaserForm CoCrF75 (A), literature basis
    value: 14
    unit: W/(m.K)
    scope: material
    conditions:
      temperature: 20 °C (120 °F)
      basis: footnote 5 says values are based on literature
      unit_in_source: 14 W/(m.K)
    method: Value printed in a manufacturer datasheet, which marks thermal values as based on literature
    status: ground
    source: 3dsystems-cocrf75
    where: Thermal Properties table, Thermal conductivity row at 20 °C / 120 °F
  - benchmark: cte
    label: Coefficient of thermal expansion, 20 to 600 °C, LaserForm CoCrF75 (A), literature basis
    value: 14
    unit: µm/(m.°C)
    scope: material
    conditions:
      temperature_range: 20 to 600 °C
      basis: footnote 5 says values are based on literature
      unit_in_source: 14 µm/(m.°C)
    method: Value printed in a manufacturer datasheet, which marks thermal values as based on literature
    status: ground
    source: 3dsystems-cocrf75
    where: Thermal Properties table, CTE row, in the range of 20 to 600 °C
  - benchmark: electrical_resistivity
    label: Electrical resistivity, LaserForm CoCrF75 (A), literature basis
    value: 874
    unit: nΩ.m
    scope: material
    conditions:
      basis: footnote 5 says values are based on literature
      temperature: not stated
      unit_in_source: 874 nΩ.m
    method: Value printed in a manufacturer datasheet, which marks electrical values as based on literature
    status: ground
    source: 3dsystems-cocrf75
    where: Electrical Properties table, Electrical resistivity row
corrosion:
  - environment: Simulated body fluid, artificial saliva and fetal bovine serum (static immersion, CoCrMo alloy, not an F75 cast part)
    headline: In simulated body fluid, the passive oxide layer on CoCrMo kept chromium release to a negligible amount, and cobalt was released most.
    effect: Gurel et al. immersed a CoCrMo alloy (27 wt% Cr, 6 wt% Mo, balance Co) in artificial saliva, simulated body fluid (SBF) and fetal bovine serum (FBS). They report that the passive oxide layer limits chromium release into SBF to a negligible amount, and that cobalt gave the highest ion release in all three fluids. In FBS, chromium release could not be stopped after the second week.
    rating: low
    conditions:
      alloy: CoCrMo medium entropy alloy, vacuum arc re-melted, 27 wt% Cr, 6 wt% Mo, balance Co (not ASTM F75 cast)
      temperature: 37 °C
      test: static immersion with ICP-MS ion release after 1, 7, 14 and 28 days
    source: toker2022
    where: Introduction; Materials and methods section 2; Results, ion release (Fig. 2)
  - environment: Air and high temperature
    headline: The high chromium content gives the alloy very good general corrosion and temperature resistance, according to VDM.
    effect: VDM states that, because of its high chromium content, CoCr F75 has very good general corrosion and temperature resistance. The datasheet gives no corrosion rate, test medium or duration.
    rating: low
    conditions:
      basis: general statement in a producer's data sheet; no test medium or rate
    source: vdm-f75
    where: Corrosion resistance section
  - environment: Body fluids (passive film on the surface)
    headline: 3D Systems says the alloy forms a passive film that makes it corrosion resistant and biocompatible.
    effect: The 3D Systems datasheet says cobalt-chromium-molybdenum alloys spontaneously form a protective passive film, which makes LaserForm CoCrF75 (A) both corrosion resistant and biocompatible. It gives no corrosion rate.
    rating: low
    conditions:
      product: LaserForm CoCrF75 (A), additive material
      basis: qualitative statement in the material description
    source: 3dsystems-cocrf75
    where: Material Description, first page
risks:
  hazards:
    - text: Implats safety data sheet for cobalt metal powder (CAS 7440-48-4; this is the powder, not the solid alloy) lists H302 harmful if swallowed, H334 may cause allergy or asthma symptoms or breathing difficulties if inhaled, H317 may cause an allergic skin reaction and H413 may cause long lasting harmful effects to aquatic life. Its signal word is DANGER. Its label section gives H301 where its hazard section gives H302.
      ghs:
        - H302
        - H334
        - H317
        - H413
      source: implats-co-sds
      where: Section 2 hazard identification (health statements and label block)
    - text: The same sheet states that cobalt and cobalt compounds are classified as possibly carcinogenic to humans (IARC Group 2B), and that over-exposure to cobalt can cause respiratory sensitisation with asthma-like symptoms.
      ghs: []
      source: implats-co-sds
      where: Specific hazards text, and Health Hazards entries for inhalation and skin
    - text: The Ted Pella cobalt safety data sheet classifies cobalt in the form of pieces, pellets, shot, sheet, foil, rod, wire and target as 'Not classified as hazard'. That is pure cobalt, not the CoCrMo alloy, so it is recorded here only as the solid-metal classification the sheet gives.
      ghs: []
      source: tedpella-cobalt
      where: Section 2.1 Classification of the substance or mixture
    - text: The same Ted Pella sheet gives a different classification for the powder form, with H317, H334 and H351 and the signal word DANGER. Its H351 (suspected of causing cancer) differs from the Implats sheet, which gives H302 and H413 for cobalt powder, so the two sheets disagree on the hazard codes and both are recorded.
      ghs:
        - H317
        - H334
        - H351
      source: tedpella-cobalt
      where: Section 2.3 Label elements for powder, Hazard Statements for powder
  failure_risks:
    - mode: Release of cobalt and chromium ions from the alloy in body fluids
      trigger: Long immersion in artificial saliva, simulated body fluid or fetal bovine serum
      consequence: Gurel et al. report that cobalt gave the highest ion release in all three fluids and that chromium release into FBS continued after the second week. The introduction says wear debris and metal ions have been associated with implant loosening. The paper gives no rate for release in an implant.
      severity: moderate
      source: toker2022
      where: Introduction; Results, ion release (Fig. 2)
    - mode: Respiratory sensitisation from inhaled cobalt powder or dust
      trigger: Breathing cobalt powder or dust during handling of the powder form
      consequence: The cobalt powder sheet lists H334 (may cause allergy or asthma symptoms or breathing difficulties if inhaled) and says over-exposure can cause respiratory sensitisation with asthma-like symptoms.
      severity: moderate
      source: implats-co-sds
      where: Section 2 health statements; Health Hazards, Inhalation
  side_effects:
    - text: The cobalt powder sheet says cobalt has been reported to cause dermatitis and skin sensitisation, and that chronic over-exposure may result in 'Cobalt itch'.
      affects: Workers who handle cobalt powder
      source: implats-co-sds
      where: Health Hazards, Skin
  handling:
    - text: The cobalt powder sheet says to avoid breathing dust or fume (precautionary statement P261), and to use mechanical extraction ventilation where a dust inhalation hazard exists. It advises dust-proof goggles and PVC or rubber gloves.
      source: implats-co-sds
      where: Section 2 precautionary statements; Exposure Controls and PPE
    - text: The cobalt powder sheet says to store the powder in a cool, dry, well-ventilated area, away from oxidising agents, alkalis and acids.
      source: implats-co-sds
      where: Handling and Storage, Storage
  mitigations: []
uses:
  - application: in-space-manufacturing
    device: Powder for laser powder-bed additive manufacturing
    example: VDM sells its CoCr F75 powder as spherical particles in standard fractions of 15-53 and 53-150 µm, for additive manufacturing. 3D Systems sells LaserForm CoCrF75 (A) for its ProX DMP 320 printer.
    source: vdm-f75
    where: Introduction; Availability and Standard particle fractions table
  - application: propulsion-and-tanks
    device: Gas turbine nozzles and vanes
    example: 'VDM lists high-temperature engineering uses for the alloy: gas nozzles and vanes for industrial gas turbines, and aero- and land-based gas turbines.'
    source: vdm-f75
    where: Applications section
  - application: structures
    device: 'Surgical implants: knee implants, metal-to-metal hip joints and dental prostheses (ground use, not space)'
    example: VDM lists knee implants, metal-to-metal hip joints and dental prosthetics as intended uses. ICAST lists the cast grade for surgical implants, and for valve, pump, general engineering and automotive parts.
    source: icast-f75
    where: VDM Applications section; ICAST Application line
supply:
  - subject: Cobalt
    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. In the United States, 51% of cobalt consumed was used in superalloys, mainly for aircraft gas turbine engines.'
    substitutes:
      - 'USGS: substitution could result in a loss in product performance or increased cost; nickel-base alloys or ceramics are named as potential substitutes in jet engines.'
    source: usgs-mcs2026-cobalt
    where: Events, Trends, and Issues (Congo (Kinshasa) 73% and Indonesia 14% of world total, 2025); Domestic Production and Use (51% superalloys); Recycling; Substitutes
  - subject: Chromium
    producers:
      - country: South Africa
        share_percent: 45.1
        year: 2025
    critical_lists: []
    recycling: 'USGS: recycled chromium in reported stainless-steel scrap receipts accounted for 21% of apparent consumption in 2025.'
    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 (South Africa 23,000 of 51,000 thousand t world total; the share of 45.1% is calculated by Space Mushroom); Recycling; Substitutes
documents:
  - title: VDM Powder CoCr F75, Material Data Sheet No. 2006, Revision 03 (VDM Metals International GmbH, November 2020)
    type: datasheet
    url: https://vdm-metals.com/fileadmin/user_upload/Downloads/Data_Sheets/Data_Sheet_VDM_Powder_CoCr_F75.pdf
    year: 2020
  - title: 'ASTM F 75 R30075: Cobalt-28 Chromium-6 Molybdenum Casting Alloy and Cast Products for Surgical Implants (ICAST Alloys LLP)'
    type: datasheet
    url: https://icastllp.com/material_db_pdf/ASTM%20F%2075%20R30075.pdf
  - title: LaserForm CoCrF75 (A) datasheet, 3D Systems (PN 10101A, 03-17)
    type: datasheet
    url: https://3dsystems.com/sites/default/files/2017-03/3D-Systems_LaserForm_CoCrF75(A)_DATASHEET_USEN_2017.03.13_WEB.pdf
    year: 2017
  - title: 'Gurel et al., From corrosion behavior to radiation response: A comprehensive biocompatibility assessment of a CoCrMo medium entropy alloy, Intermetallics 149 (2022) 107680'
    type: paper
    url: https://tatum.ogu.edu.tr/Storage/tatum/Uploads/From-corrosion-behavior-to-radiation-response-A-comprehensive-Mine-Toker-2022.pdf
    year: 2022
  - title: 'Hazard data sheet: Cobalt powder (Impala Base Metals Refinery, MAN-HDS-001, revision 19)'
    type: sds
    url: https://www.implats.co.za/pdf/material-safety-data-sheets/hazard-data-sheet-cobalt-powder.pdf
  - title: 'USGS Mineral Commodity Summaries 2026: Cobalt'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-cobalt.pdf
    year: 2026
  - title: 'USGS Mineral Commodity Summaries 2026: Chromium'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
    year: 2026
  - title: Safety Data Sheet, Cobalt Products (Ted Pella, Inc.), pieces and powder classification
    type: sds
    url: https://www.tedpella.com/SDS_html/29-27_9570_Cobalt_Products_sds.pdf
    year: 2017
gaps:
  - The cast ASTM F75 values are minimums printed by ICAST. No cast-grade modulus, thermal conductivity, thermal expansion or electrical resistivity was found in a cast-grade source; the 3D Systems values are for laser-sintered parts and are labelled that way.
  - No ASTM F75 standard text was opened, so the cast heat-treatment conditions (as-cast or annealed) are as printed by ICAST and not separated by temper.
  - No safety data sheet for the solid CoCrMo alloy was read. The hazard classes are for cobalt metal powder (Implats, CAS 7440-48-4; Ted Pella) and do not apply to the solid alloy by default. The Ted Pella sheet covers pure cobalt pieces, not the CoCrMo alloy, and classes them as not hazardous.
  - The cobalt powder sheet's label section gives H301 and its hazard section gives H302 for acute oral toxicity; both are recorded and not resolved.
  - The Gurel et al. alloy is an arc-melted CoCrMo medium entropy alloy, not an ASTM F75 cast part. Its corrosion result is qualitative, and the ion release rates are shown only in a figure, so no rate is recorded.
  - The IYTE paper on nitrogen-implanted CoCrMo could not be read in this run (the PDF returned no text), so its oxide film thickness is not recorded.
  - No fatigue, creep, wear-rate, hot-strength or stress-rupture value for ASTM F75 was found in a source we could open.
  - No vacuum, outgassing, radiation or flight result for CoCrMo was found. The 3D Systems datasheet is a ground material sheet, not a flight result.
  - Hardness is recorded for the cast grade only (25 to 35 HRC, ICAST); the 3D Systems hardness values were not recorded. Hardness has no canonical name in spores/property-canon.yaml, so hardness_rockwell_c is used.
  - Oxygen content is recorded for the VDM powder as an upper limit only. oxygen_content has no canonical name in spores/property-canon.yaml.
  - Critical-mineral listings for cobalt and chromium (USGS 2025 list and EU list) were not read in this run, so critical_lists is empty.
  - Molybdenum supply and producer shares were not read. The chromium share of 45.1% is calculated by Space Mushroom from the USGS table and is labelled as calculated.
  - The ETP, wrought ASTM F1537 and R31538 (listed by VDM against this powder) data were not recorded, since they are separate product forms in the sources read.
sources:
  vdm-f75:
    title: VDM Powder CoCr F75, Material Data Sheet No. 2006, Revision 03
    id: VDM Metals International GmbH, November 2020; designations ISO 5832-12 / 5832-4, ASTM F1537-11 / F75, UNS R31538 / R30075
    url: https://vdm-metals.com/fileadmin/user_upload/Downloads/Data_Sheets/Data_Sheet_VDM_Powder_CoCr_F75.pdf
    year: 2020
    kind: datasheet
    license: producer data sheet (cited, not reproduced)
  icast-f75:
    title: 'ASTM F 75 R30075: Standard Specification for Cobalt-28 Chromium-6 Molybdenum Casting Alloy and Cast Products for Surgical Implants'
    id: ICAST Alloys LLP material database; UNS R30075, JIS 7402-1
    url: https://icastllp.com/material_db_pdf/ASTM%20F%2075%20R30075.pdf
    kind: datasheet
    license: producer data sheet (cited, not reproduced)
  3dsystems-cocrf75:
    title: LaserForm CoCrF75 (A) datasheet, 3D Systems, for ProX DMP 320 metal printers
    id: PN 10101A, 03-17; values for laser-sintered parts
    url: https://3dsystems.com/sites/default/files/2017-03/3D-Systems_LaserForm_CoCrF75(A)_DATASHEET_USEN_2017.03.13_WEB.pdf
    year: 2017
    kind: datasheet
    license: producer data sheet (cited, not reproduced)
  toker2022:
    title: 'From corrosion behavior to radiation response: A comprehensive biocompatibility assessment of a CoCrMo medium entropy alloy for utility in orthopedic and dental implants'
    id: Gurel et al., Intermetallics 149 (2022) 107680
    url: https://tatum.ogu.edu.tr/Storage/tatum/Uploads/From-corrosion-behavior-to-radiation-response-A-comprehensive-Mine-Toker-2022.pdf
    year: 2022
    kind: paper
    license: journal article (cited, not reproduced)
  implats-co-sds:
    title: 'Hazard data sheet: Cobalt powder, Impala Base Metals Refinery (MAN-HDS-001, revision 19, last reviewed 08-Jan-2018)'
    id: CAS 7440-48-4
    url: https://www.implats.co.za/pdf/material-safety-data-sheets/hazard-data-sheet-cobalt-powder.pdf
    kind: datasheet
    license: supplier document (cited, not reproduced)
  usgs-mcs2026-cobalt:
    title: 'Mineral Commodity Summaries 2026: Cobalt'
    id: USGS MCS 2026, 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'
    id: USGS MCS 2026, February 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  tedpella-cobalt:
    title: Safety Data Sheet, Cobalt Products (Ted Pella, Inc.), pieces and powder classification
    id: CAS 7440-48-4; issue date 2015, review date 2017
    url: https://www.tedpella.com/SDS_html/29-27_9570_Cobalt_Products_sds.pdf
    year: 2017
    kind: datasheet
    license: supplier document (cited, not reproduced)
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 15
  unreachable: 0
  caveats: 3
  note: 'Read by an AI assistant on 2026-11-01 from the datasheets and pages named in each entry (PDFs extracted with pdftotext). Caveats: the cast values are ICAST minimums, the additive values come from one manufacturer sheet, and the hazard entry is for cobalt powder, not the solid alloy.'
story:
  recipe:
    line: ASTM F75 is a cobalt-base alloy. Cobalt is the balance, and chromium and molybdenum are the main alloying elements, with the ASTM F75 limits printed in weight percent by VDM and ICAST. The cast grade is made by casting for surgical implants; the VDM powder is made as spherical particles for additive manufacturing.
    parts:
      - name: Cobalt
        symbol: Co
        role: The matrix of the alloy. The ASTM F75 limits give cobalt only as the balance, so no numeric share is given.
      - name: Chromium
        symbol: Cr
        share_percent: 27
        share_high: 30
        role: Gives the alloy its passive oxide film. VDM credits its high chromium content with very good general corrosion and temperature resistance.
      - name: Molybdenum
        symbol: Mo
        share_percent: 5
        share_high: 7
        role: A listed alloying element in the ASTM F75 composition. The sources read here do not separate its effect from the rest of the alloy.
  risk_groups:
    - title: For people
      level: 1
      verdict: Cobalt powder is classified; solid alloy not checked
      lead: The hazard classes read here are for cobalt metal powder, from a supplier's safety data sheet. No safety data sheet for the solid CoCrMo alloy was read in this run.
      points:
        - label: Powder
          line: The cobalt powder sheet (CAS 7440-48-4) lists H302, H334, H317 and H413 with the signal word DANGER. Its label section gives H301 where its hazard section gives H302.
        - label: Cancer
          line: The same sheet says cobalt and cobalt compounds are classified as possibly carcinogenic to humans (IARC Group 2B).
        - label: Breathing
          line: The sheet warns that over-exposure to cobalt can cause respiratory sensitisation with asthma-like symptoms.
        - label: Solid cobalt
          line: A Ted Pella sheet for pure cobalt pieces, sheet and rod (not the CoCrMo alloy) gives no GHS hazard class, while its powder entry carries H317, H334 and H351 with the signal word DANGER.
    - title: If the alloy meets body fluid
      lead: These results come from static immersion tests in laboratory fluids, not from implant patients.
      points:
        - label: Cobalt release
          line: In a CoCrMo alloy (27 wt% Cr, 6 wt% Mo, balance Co), cobalt gave the highest ion release in artificial saliva, simulated body fluid and fetal bovine serum. Chromium release into simulated body fluid stayed negligible.
        - label: Chromium later
          line: In fetal bovine serum, chromium release continued after the second week, so the oxide layer did not stop it there.
    - title: Handling and storage
      points:
        - label: Dust
          line: Avoid breathing dust or fume. Use mechanical extraction ventilation where a dust inhalation hazard exists, and wear dust-proof goggles and PVC or rubber gloves (cobalt powder sheet).
        - label: Storage
          line: Keep the powder in a cool, dry, well-ventilated area, away from oxidising agents, alkalis and acids (cobalt powder sheet).
  why: ASTM F75 (UNS R30075) is a cobalt-chromium-molybdenum casting alloy, written as Co-28Cr-6Mo, for surgical implants. The cast grade has a minimum tensile strength of 655 MPa and a minimum yield strength of 450 MPa, according to the ICAST data sheet. The same composition is sold by VDM as a powder for additive manufacturing, with a density of 8.3 g/cm3 at 20 °C. VDM credits the chromium content with very good general corrosion and temperature resistance.
  uses:
    - where: Additive manufacturing powder
      line: VDM sells its CoCr F75 powder as spherical particles in standard fractions of 15-53 and 53-150 µm, for additive manufacturing. 3D Systems sells LaserForm CoCrF75 (A) for its ProX DMP 320 printer.
    - where: Gas turbine nozzles and vanes
      line: 'VDM lists high-temperature engineering uses for the alloy: gas nozzles and vanes for industrial gas turbines, and aero- and land-based gas turbines.'
    - where: Surgical implants
      line: VDM lists knee implants, metal-to-metal hip joints and dental prosthetics as intended uses. ICAST lists the cast grade for surgical implants, and for valve, pump, general engineering and automotive parts.
  can_do:
    - label: Strength
      line: Carries a minimum tensile strength of 655 MPa and a minimum yield strength of 450 MPa as cast (ICAST).
    - label: Stiffness
      line: Has a Young's modulus of 225 GPa (±5 GPa) in laser-sintered parts after annealing (3D Systems). This is an additive value, not a cast value.
    - label: Melting range
      line: Melts between 1350 and 1430 °C as a powder (VDM).
    - label: Hardness
      line: Reaches a hardness of 25 to 35 HRC as cast (ICAST).
  compare: LaserForm CoCrF75 (A) from 3D Systems, a laser-sintered material, has a yield strength of 540 MPa after annealing in the horizontal build direction. The cast F75 minimum is 450 MPa (ICAST). The two sources describe different product forms, so the difference is not a ranking of processes. The densities are 8.35 g/cm3 (theoretical, 3D Systems) and 8.3 g/cm3 (VDM powder).
  compare_rows:
    - label: Density
      benchmark: density
    - label: Yield strength
      benchmark: yield_strength
    - label: Young's modulus
      benchmark: elastic_modulus
  handling:
    - Avoid breathing dust or fume, and use mechanical extraction ventilation where dust is a hazard (cobalt powder sheet).
    - Keep cobalt powder in a cool, dry, well-ventilated area, away from oxidising agents, alkalis and acids.
    - Use the supplier's safety data sheet for the alloy you buy; no sheet for the solid alloy was read here.
  good_for:
    - 'Implant parts: a minimum tensile strength of 655 MPa and a minimum yield strength of 450 MPa as cast (ICAST).'
    - 'Corrosion-resistant metal parts with high chromium: VDM gives very good general corrosion and temperature resistance.'
  watch_out:
    - Cobalt is released in body-fluid tests, and chromium release continues in fetal bovine serum after the second week.
    - The mechanical values are cast minimums or additive datasheet values, not a full property set for the cast grade.
    - The powder carries the classified cobalt hazards, including H334 for respiratory sensitisation.
  verdict: ASTM F75 has cast minimum strengths of 655 MPa tensile and 450 MPa yield (ICAST). Its cobalt powder carries sensitisation hazards, and cast values beyond minimums were not found.