spore: profile
id: titanium-grade-3
spore_version: 0.2
family: titanium-alloys
name: Commercially pure titanium, Grade 3 (UNS R50550)
abbreviation: CP Ti Grade 3
role: higher-strength unalloyed metal
category: metals
type: titanium
summary: |
  Commercially pure (CP) titanium Grade 3, UNS R50550, is unalloyed titanium with a higher oxygen limit than Grades 1 and 2. ASTM B265 sets its minimum tensile strength at 450 MPa and its minimum 0.2 % yield strength at 380 MPa, with 18 % minimum elongation for strip, sheet and plate. The Smiths datasheet gives typical values of 593 MPa tensile and 462 MPa yield, and a density of 4.51 g/cc. Alleima describes the grade as having medium oxygen content and as typically used for matrix plates in shell and tube heat exchangers.
best_for: Formed and welded parts that need more strength than Grade 2 while keeping weldability and corrosion resistance in oxidising, neutral and mildly reducing media (Smiths)
weakest_at: 'Strength: 450 MPa minimum tensile, well below Ti-6Al-4V (see the Ti-6Al-4V profile). Oxygen limit of 0.35 %, the highest of CP grades 1 to 3 in ASTM B265 Table 2'
identity:
  formula: 'Unalloyed titanium, UNS R50550 (ASTM Grade 3): maximum limits on O, Fe, C, N and H, titanium the balance'
  cas: 7440-32-6
  source: astm-b265
  where: Table 2 Chemical Requirements, Grade 3 column (ASTM B265-08b copy); CAS from PubChem CID 23963 (pubchem-ti)
  designations:
    - system: UNS
      code: R50550
      source: smith-cp3
      where: Material Specifications list, UNS R50550 line
    - system: EN
      code: '3.7055'
      source: smith-cp3
      where: Material Specifications list, W. Nr. 3.7055 line
    - system: Name
      code: CP Grade 3
      source: smith-cp3
      where: Title, CP Grade 3 Technical Datasheet
    - system: Trade name
      code: ATI 55
      source: ati-cp3
      where: Page title, ATI 55, CP Grade 3 Titanium
    - system: Trade name
      code: Ti Grade 3
      source: alleima-ti3
      where: Datasheet title, Alleima Ti Grade 3, tube and pipe, seamless
    - system: ASTM
      code: B265
      note: strip, sheet and plate
      source: astm-b265
      where: Title, B 265 - 08b; Table 1 and Table 2, Grade 3 row and column
    - system: ASTM
      code: B348
      note: bars and billets
      source: ati-cp3
      where: Bar and billet specifications list, ASTM B 348 line
    - system: ASTM
      code: F67
      note: bar, plate and sheet
      source: ati-cp3
      where: Bar, plate and sheet specifications list, ASTM F 67 line
    - system: ASME
      code: SB-265
      note: plate, strip and sheet
      source: ati-cp3
      where: Plate specifications list, ASME SB-265 line
    - system: AMS
      code: '4900'
      note: plate, sheet and strip
      source: ati-cp3
      where: Plate, sheet and strip specifications list, AMS 4900 line
    - system: AMS
      code: '4921'
      note: bar
      source: ati-cp3
      where: Bar specifications list, AMS 4921 line
tags:
  environments: []
  stresses: []
  applications:
    - thermal-control
    - structures
properties:
  - benchmark: density
    label: Density
    value: 4.51
    unit: g/cm3
    scope: material
    conditions:
      form: CP Grade 3 product (datasheet product range)
      condition: not stated
      unit_in_source: g/cc
    method: Printed as 4.51 g/cc in the product description of the Smiths CP Grade 3 datasheet. The ATI page prints 0.163 lb/in3 (4.51 g/cm3) for all forms, and the UPM datasheet prints 4.512 g/cm3.
    status: ground
    source: smith-cp3
    where: Product Description, first paragraph
  - benchmark: elastic_modulus
    label: Elastic modulus, typical
    value: 103
    unit: GPa
    scope: material
    conditions:
      form: CP Grade 3 product (datasheet product range)
      basis: typical, not a minimum
      loading: not stated
    method: Printed as typical 103 GPa in the Mechanical Properties table of the Smiths datasheet. The UPM datasheet prints 15.2 to 17.4 Msi, which is not converted here.
    status: ground
    source: smith-cp3
    where: Mechanical Properties table, Elastic modulus GPa row, typical column
  - benchmark: beta_transus
    label: Beta transus
    value: 1690
    unit: °F
    scope: material
    conditions:
      form: sheet and coil (AMS 4900 datasheet)
      condition: not stated
    method: Printed as 1690 under the T (°F) column of the Physical Properties table of the UPM datasheet. The table prints no Celsius value, so none is given. beta_transus is not in the canonical list (see gaps).
    status: ground
    source: upm-cp3
    where: Physical Properties table, Beta Transus row
  - benchmark: cte
    label: Mean coefficient of thermal expansion, 20 to 100 °C
    value: 8.6
    unit: 10-6/°C
    scope: material
    conditions:
      temperature: 20 to 100 °C (printed 68 to 212 °F)
      basis: mean coefficient
      unit_in_source: m m-1 °C-1
    method: Printed as 8.6x10-6 m/m°C for 20 to 100 °C in the Physical Properties table of the UPM datasheet, beside 4.8x10-6 in/in°F. The 20 to 300 °C and 20 to 500 °C rows (9.5 and 9.7) are not recorded.
    status: ground
    source: upm-cp3
    where: Physical Properties table, Mean Coefficient of Thermal Expansion row, 68-212 F (20-100 C)
  - benchmark: thermal_conductivity
    label: Thermal conductivity
    value: 151.2
    unit: Btu-in/(hr·ft²·°F)
    scope: material
    conditions:
      temperature: not stated (table dash)
      unit_in_source: Btu-in/hr ft2- °F
    method: Printed as 151.2 Btu-in/hr ft2-F in the Physical Properties table of the UPM datasheet. No SI value is printed; the importer converts from the printed unit.
    status: ground
    source: upm-cp3
    where: Physical Properties table, Thermal Conductivity row
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, minimum (strip, sheet and plate)
    value: 450
    bound: lower
    unit: MPa
    scope: material
    conditions:
      form: strip, sheet and plate (ASTM B265 product)
      condition: as specified for Grade 3 in ASTM B265-08b Table 1
      minimum: 'yes'
    method: Minimum in Table 1 (Tensile Requirements) of the ASTM B265-08b copy, Grade 3 row, with 65 ksi printed beside 450 MPa. The ATI page prints the same 65 ksi and 450 MPa minimum for all forms.
    status: ground
    source: astm-b265
    where: Table 1 Tensile Requirements, Grade 3 row, tensile strength min (ksi 65, MPa 450)
  - benchmark: yield_strength
    label: Yield strength, 0.2 % offset, minimum (strip, sheet and plate)
    value: 380
    bound: lower
    unit: MPa
    scope: material
    conditions:
      form: strip, sheet and plate (ASTM B265 product)
      offset: 0.2 %
      minimum: 'yes'
    method: Minimum in Table 1 of the ASTM B265-08b copy, Grade 3 row, with 55 ksi printed beside 380 MPa. The maximum of 80 ksi (550 MPa) in the same row is not recorded.
    status: ground
    source: astm-b265
    where: Table 1 Tensile Requirements, Grade 3 row, yield strength 0.2 % offset min (ksi 55, MPa 380)
  - benchmark: elongation
    label: Elongation, minimum (strip, sheet and plate)
    value: 18
    bound: lower
    unit: '%'
    scope: material
    conditions:
      form: strip, sheet and plate (ASTM B265 product)
      gauge: 2 in or 50 mm
      minimum: 'yes'
    method: Minimum elongation in Table 1 of the ASTM B265-08b copy, Grade 3 row.
    status: ground
    source: astm-b265
    where: Table 1 Tensile Requirements, Grade 3 row, elongation in 2 in. or 50 mm min %
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, typical
    value: 593
    unit: MPa
    scope: material
    conditions:
      form: CP Grade 3 product (datasheet product range)
      basis: typical, not a minimum
    method: Printed as typical 593 MPa in the UTS row of the Smiths datasheet mechanical properties table. The Smiths minimum of 448 MPa is not used; the ASTM minimum of 450 MPa is recorded instead.
    status: ground
    source: smith-cp3
    where: Mechanical Properties table, UTS MPa row, typical column
  - benchmark: yield_strength
    label: Yield strength, 0.2 % offset, typical
    value: 462
    unit: MPa
    scope: material
    conditions:
      form: CP Grade 3 product (datasheet product range)
      offset: 0.2 %
      basis: typical, not a minimum
    method: Printed as typical 462 MPa in the 0.2% PS row of the Smiths datasheet, and again in its product description. The Smiths minimum of 379 MPa is not used; the ASTM minimum of 380 MPa is recorded instead.
    status: ground
    source: smith-cp3
    where: Mechanical Properties table, 0.2% PS MPa row, typical column
  - benchmark: elongation
    label: Elongation, typical
    value: 25
    unit: '%'
    scope: material
    conditions:
      form: CP Grade 3 product (datasheet product range)
      gauge: 2 in
      basis: typical, not a minimum
    method: Printed in the Elongation on 2 in row, typical column, of the Smiths CP Grade 3 datasheet.
    status: ground
    source: smith-cp3
    where: Mechanical Properties table, Elongation on 2 in % row, typical column
  - benchmark: reduction_of_area
    label: Reduction of area, minimum
    value: 35
    bound: lower
    unit: '%'
    scope: material
    conditions:
      form: CP Grade 3 product (datasheet product range)
      condition: minimum as printed; no separate condition given
      minimum: 'yes'
    method: Printed in the Mechanical Properties table of the Smiths CP Grade 3 datasheet. reduction_of_area is not in the canonical list, so a snake_case name is used (see gaps).
    status: ground
    source: smith-cp3
    where: Mechanical Properties table, Reduction of area row, minimum column
  - benchmark: impact_energy
    label: Charpy V-notch impact, minimum
    value: 20
    bound: lower
    unit: J
    scope: material
    conditions:
      form: CP Grade 3 product (datasheet product range)
      test: Charpy V-notch
      minimum: 'yes'
    method: Printed in the Mechanical Properties table of the Smiths CP Grade 3 datasheet. impact_energy is a snake_case name (see gaps).
    status: ground
    source: smith-cp3
    where: Mechanical Properties table, Charpy V notch impact row, minimum column
  - benchmark: hardness
    label: Hardness, typical
    value: 200
    unit: HV
    scope: material
    conditions:
      form: CP Grade 3 product (datasheet product range)
      basis: typical
    method: Printed as typical 200 HV in the Hardness HV row of the Smiths datasheet mechanical properties table. hardness is a snake_case name (see gaps).
    status: ground
    source: smith-cp3
    where: Mechanical Properties table, Hardness HV row, typical column
  - benchmark: hardness
    label: Hardness, maximum (bar and billet)
    value: 90
    bound: upper
    unit: HRB
    scope: material
    conditions:
      form: bar and billet only (ATI page)
      condition: as supplied; no separate condition given
    method: Printed as 90 HRB max. in the Properties list of the ATI page, for bar and billet only. The page gives no hardness value for plate, sheet or strip.
    status: ground
    source: ati-cp3
    where: Properties list, Hardness (bar and billet only) row
corrosion:
  - environment: Oxidising, neutral and mildly reducing media, including chlorides
    headline: High corrosion resistance in oxidising, neutral and mildly reducing media, including chlorides.
    effect: Smiths says the grade offers high corrosion resistance in oxidising, neutral and mildly reducing media, including chlorides. The datasheet prints no test conditions.
    rating: low
    conditions:
      basis: manufacturer statement; no test conditions printed
      form: CP Grade 3 product (Smiths datasheet)
    source: smith-cp3
    where: Corrosion Resistance section
  - environment: Seawater and common salt solutions, pH 3 to 12 (general statement for titanium alloys)
    headline: 'General statement for titanium alloys: resists common salt solutions and chlorides from pH 3 to 12.'
    effect: Titanium Industries says titanium alloys are expected to resist common salt solutions, chlorides and other listed solutions that have a pH range of 3 to 12. The page gives no statement specific to Grade 3 or to commercially pure titanium.
    rating: low
    conditions:
      basis: general statement for titanium alloys; no Grade 3 test
      pH: 3 to 12
    source: titanium-industries
    where: Titanium Performance in Seawater Applications, corrosion statements
  - environment: Chloride stress corrosion (general statement for titanium)
    headline: 'General statement: titanium does not show the same chloride stress-corrosion susceptibility as stainless steel.'
    effect: Titanium Industries says titanium does not demonstrate the same susceptibility to stress corrosion from chlorides as stainless steel. The statement is for titanium in general, not a Grade 3 test.
    rating: low
    conditions:
      basis: general statement for titanium; no test conditions printed
    source: titanium-industries
    where: Titanium Performance in Seawater Applications, corrosion statements
risks:
  hazards:
    - text: PubChem gives titanium (CID 23963) hazard statement H228, flammable solid, with signal word Danger and classification Flammable solids Category 1. The record does not separate bulk metal from powder or swarf, so check the safety data sheet for the form handled.
      ghs:
        - 'H228: Flammable solid'
      source: pubchem-ti
      where: Safety and Hazards, GHS Classification (CID 23963)
    - text: PubChem reports that 606 of 808 company reports did not meet GHS hazard criteria, and 202 of 808 reports carried hazard statement codes.
      ghs: []
      source: pubchem-ti
      where: Safety and Hazards, GHS Classification, report counts
    - text: Precautionary statement codes listed with the GHS entry include P210, P222, P231, P233, P235, P240, P241 and P280.
      ghs: []
      source: pubchem-ti
      where: Safety and Hazards, GHS precautionary statements
  failure_risks:
    - mode: Bending tighter than the specified radius
      trigger: Bending thin sheet or strip tighter than 2T (under 0.070 in) or tighter than 2.5T (0.070 to 0.187 in)
      consequence: ASTM B265 Table 1 sets the bend-test radii for Grade 3. The standard prints no failure data for tighter bends.
      severity: moderate
      source: astm-b265
      where: Table 1 Tensile Requirements, Bend Test column, Grade 3 row
    - mode: Use in media outside the stated range
      trigger: Strongly reducing media (outside oxidising, neutral and mildly reducing media)
      consequence: Smiths rates corrosion resistance only for oxidising, neutral and mildly reducing media, including chlorides. It prints no data for strongly reducing media.
      severity: moderate
      source: smith-cp3
      where: Corrosion Resistance section
  side_effects: []
  handling:
    - text: Weldability is excellent. Specified bend radius is 2.0 times thickness for sections under 0.070 in and 2.5 times above that. Welded bend radius is 3.0 times thickness at minimum.
      source: smith-cp3
      where: Fabrication section
    - text: ASTM B265 bend-test radii for Grade 3 are 2T for thickness under 0.070 in and 2.5T for 0.070 to 0.187 in.
      source: astm-b265
      where: Table 1 Tensile Requirements, Bend Test column, Grade 3 row
  mitigations: []
uses:
  - application: thermal-control
    device: Matrix plates for shell and tube heat exchangers
    example: Alleima says the grade is typically used for matrix plates in shell and tube heat exchangers.
    source: alleima-ti3
    where: Datasheet description, first paragraph
  - application: structures
    device: Aerospace sheet, plate and strip to AMS 4900
    example: United Performance Metals lists aerospace structures among the industry applications for its Grade 3 sheet and coil to AMS 4900.
    source: upm-cp3
    where: Industry Applications list
  - application: structures
    device: Architecture, automotive, chemical plant and marine components and equipment
    example: Smiths lists architecture, automotive, chemical plant and marine industries among the typical applications for CP Grade 3.
    source: smith-cp3
    where: Typical Applications box
supply:
  - subject: Titanium sponge (feedstock for titanium mill products)
    producers:
      - country: China
        share_percent: 70.3
        year: 2025
        basis: 'computed: 260,000 t of 370,000 t world sponge (USGS table, World Sponge Metal Production)'
      - country: Japan
        share_percent: 14.3
        year: 2025
        basis: 'computed: 53,000 t of 370,000 t'
      - country: Russia
        share_percent: 6.8
        year: 2025
        basis: 'computed: 25,000 t of 370,000 t'
      - country: Kazakhstan
        share_percent: 4.3
        year: 2025
        basis: 'computed: 16,000 t of 370,000 t'
      - country: Saudi Arabia
        share_percent: 3.2
        year: 2025
        basis: 'computed: 12,000 t of 370,000 t'
    us_position: The United States produced no titanium sponge in 2025; the last domestic sponge plant closed in 2024. U.S. imports of sponge were an estimated 44,000 tons in 2025 (Japan 73 %, Kazakhstan 13 %, Saudi Arabia 13 % through July 2025).
    source: usgs-ti-2026
    where: Domestic Production and Use; Events, Trends, and Issues; World Sponge Metal Production table (2025e)
media: []
documents:
  - title: 'Smiths Metal Centres: CP Grade 3 technical datasheet'
    type: datasheet
    url: https://www.smithmetal.com/pdf/titanium/cp-grade-3.pdf
    year: 2023
  - title: 'Alleima: Ti Grade 3 seamless tube and pipe datasheet (updated 2025-05-09)'
    type: datasheet
    url: https://alleima.com/en/technical-center/material-datasheets/tube-and-pipe-seamless/alleima-ti-grade-3?show=pdf
    year: 2025
  - title: 'ASTM B265-08b: Titanium and Titanium Alloy Strip, Sheet, and Plate (copy hosted by GS Alloy)'
    type: standard
    url: https://gsalloy.com/wp-content/uploads/2024/04/ASTM-B265.pdf
    year: 2008
  - title: 'United Performance Metals: CP Grade 3 (AMS 4900, UNS R50550) datasheet'
    type: datasheet
    url: https://www.upmet.com/sites/default/files/datasheets/cp-grade-3.pdf
    year: 2026
  - title: 'ATI: ATI 55, CP Grade 3 Titanium product page'
    type: datasheet
    url: https://www.atimaterials.com/Products/ati-cp3
    year: 2026
  - title: 'USGS Mineral Commodity Summaries 2026: Titanium'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-titanium.pdf
    year: 2026
  - title: 'PubChem: Titanium (CID 23963), GHS classification (PUG View JSON)'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23963/JSON
    year: 2026
  - title: 'Titanium Industries: Titanium Performance in Seawater Applications'
    type: datasheet
    url: https://titanium.com/technical-references/titanium-seawater-applications
    year: 2026
gaps:
  - 'Melting point: not printed in any datasheet read in this run.'
  - 'Specific heat and Poisson''s ratio: no value in the datasheets read in this run.'
  - 'Thermal expansion at higher ranges: the UPM datasheet also prints 9.5 and 9.7 (10-6 m/m°C) for 20 to 300 °C and 20 to 500 °C; these are not recorded.'
  - 'Composition conflict: Alleima prints nominal Fe 0.20, O 0.205, C 0.08, H 0.01 and N 0.05. Smiths prints C 0.1, O 0.35, H 0.015 (sheet) and 0.0125 (bar). ATI prints N 0.03 for plate, sheet and strip. ASTM B265 Table 2, which UPM and ATI also match for O and Fe, is used.'
  - 'Minimum conflict: Smiths prints UTS minimum 448 MPa and 0.2 % PS minimum 379 MPa; ASTM B265 gives 450 and 380 and is used.'
  - 'Mechanical basis: the UPM row (UTS 85 ksi / 595 MPa, 0.02 % YS 65 ksi / 450 MPa, 25 % elongation, 48 % RA) does not state minimum or typical, so it is not recorded.'
  - 'Form split: Smiths values are not split by form. ASTM Table 1 covers strip, sheet and plate only. Bar tensile values from ASTM B348 were not fetched, so bar strengths are not recorded separately.'
  - 'Hardness: Smiths gives typical 200 HV and ATI gives maximum 90 HRB for bar and billet only. No hardness basis is common to both.'
  - 'Property names: hardness, reduction_of_area, impact_energy and beta_transus are not in spores/property-canon.yaml and use snake_case names.'
  - 'Crevice corrosion and chloride limits: no Grade 3 test was found in the pages read. The Titanium Industries statements are for titanium alloys in general.'
  - 'Seawater temperature limit and any chloride data for Grade 3: none found in the sources read.'
  - 'Space and orbital data (atomic oxygen erosion, outgassing, thermal cycling in orbit, cryogenic properties): no NASA or NIST source with Grade 3 numbers was fetched.'
  - 'Fatigue, hydrogen embrittlement and galling: no numeric Grade 3 values in the sources read.'
  - 'Critical-mineral lists and crustal abundance: the USGS 2026 titanium summary fetched here gives neither.'
  - Atomic weights of the constituents were not fetched, so recipe parts carry share limits only.
  - 'Process route (how sheet, bar or tube is made): not described in the sources read.'
  - 'Designations not recorded: AIR 9182 T-50 is printed by Smiths but is not an allowed designation system. Smiths prints ''ASTM 265 Grade 3'', which is a typo for B265; the ASTM copy is used for that code.'
  - 'Medical use: Smiths lists medical engineering among typical applications. It is not an allowed application, so it is not recorded as a use.'
  - 'Standard edition: the ASTM B265 copy is the 2008b edition (header B 265 - 08b). Check the current edition before specifying.'
  - 'Dates: the Smiths datasheet is dated 2023, the Alleima datasheet 2025-05-09, and the ATI page carries no date.'
sources:
  smith-cp3:
    title: CP Grade 3 Technical Datasheet (Smiths Metal Centres)
    id: Smiths Metal Centres
    url: https://www.smithmetal.com/pdf/titanium/cp-grade-3.pdf
    year: 2023
    kind: datasheet
    license: supplier datasheet, cited not reproduced
  alleima-ti3:
    title: 'Alleima Ti Grade 3, tube and pipe, seamless: datasheet (updated 2025-05-09)'
    id: Alleima
    url: https://alleima.com/en/technical-center/material-datasheets/tube-and-pipe-seamless/alleima-ti-grade-3?show=pdf
    year: 2025
    kind: datasheet
    license: supplier datasheet, cited not reproduced
  astm-b265:
    title: 'ASTM B265-08b: Standard Specification for Titanium and Titanium Alloy Strip, Sheet, and Plate (copy hosted by GS Alloy)'
    id: ASTM B265-08b
    url: https://gsalloy.com/wp-content/uploads/2024/04/ASTM-B265.pdf
    year: 2008
    kind: standard
    license: standard copy, cited not reproduced
  upm-cp3:
    title: CP Grade 3, AMS 4900 / UNS R50550 datasheet (United Performance Metals)
    id: United Performance Metals
    url: https://www.upmet.com/sites/default/files/datasheets/cp-grade-3.pdf
    year: 2026
    kind: datasheet
    license: supplier datasheet, cited not reproduced
  ati-cp3:
    title: ATI 55, CP Grade 3 Titanium (ATI product page)
    id: ATI
    url: https://www.atimaterials.com/Products/ati-cp3
    year: 2026
    kind: web
    license: supplier web page, cited not reproduced
  usgs-ti-2026:
    title: 'Mineral Commodity Summaries 2026: Titanium (USGS, February 2026)'
    id: USGS MCS 2026, Titanium
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-titanium.pdf
    year: 2026
    kind: report
    license: US Government work, public domain
  pubchem-ti:
    title: 'PubChem: Titanium (CID 23963), GHS classification and identifiers'
    id: PubChem CID 23963
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23963/JSON
    year: 2026
    kind: database
    license: PubChem, public
  titanium-industries:
    title: Titanium Performance in Seawater Applications (Titanium Industries)
    id: Titanium Industries technical data
    url: https://titanium.com/technical-references/titanium-seawater-applications
    year: 2026
    kind: web
    license: supplier web page, cited not reproduced
license: CC-BY-4.0
updated: '2026-10-26'
review:
  status: draft
  method: assistant
  checked_values: 15
  unreachable: 0
  caveats: 3
  note: 'Written 2026-10-26 by an assistant from pages fetched in this run: Smiths CP Grade 3 datasheet, Alleima Ti Grade 3 datasheet (PDF and web page), ASTM B265-08b copy (GS Alloy), UPM CP Grade 3 datasheet, ATI 55 page, USGS MCS 2026 titanium, PubChem and the Titanium Industries seawater page. Ulbrich and MakeItFrom were not fetched and are not used.'
story:
  recipe:
    line: Unalloyed titanium with no deliberate alloying additions. ASTM B265 limits Grade 3 to maximum oxygen, iron, carbon, nitrogen and hydrogen, with titanium as the balance. Process routes are not described in the sources read.
    parts:
      - name: Titanium
        symbol: Ti
        share_note: balance (the rest)
        role: Base metal. Gives the low density and the oxide-film corrosion resistance.
        source: smith-cp3
        where: Chemical Composition table, Ti balance
      - name: Oxygen
        symbol: O
        share_high: 0.35
        share_note: maximum 0.35 %
        role: Interstitial impurity with a maximum limit. ASTM B265 Table 2 gives Grade 3 the highest oxygen limit of Grades 1 to 3.
        source: astm-b265
        where: Table 2 Chemical Requirements, Oxygen max, Grade 3 column
      - name: Iron
        symbol: Fe
        share_high: 0.3
        share_note: maximum 0.3 %
        role: Impurity with a maximum limit.
        source: astm-b265
        where: Table 2 Chemical Requirements, Iron max, Grade 3 column
      - name: Carbon
        symbol: C
        share_high: 0.08
        share_note: maximum 0.08 %
        role: Interstitial impurity with a maximum limit.
        source: astm-b265
        where: Table 2 Chemical Requirements, Carbon max, Grade 3 column
      - name: Nitrogen
        symbol: 'N'
        share_high: 0.05
        share_note: maximum 0.05 %
        role: Interstitial impurity with a maximum limit. Grade 3 allows more nitrogen than Grades 1 and 2 (0.03 %).
        source: astm-b265
        where: Table 2 Chemical Requirements, Nitrogen max, Grade 3 column
      - name: Hydrogen
        symbol: H
        share_high: 0.015
        share_note: maximum 0.015 %
        role: Interstitial impurity with a maximum limit.
        source: astm-b265
        where: Table 2 Chemical Requirements, Hydrogen max, Grade 3 column
  risk_groups:
    - title: For people
      level: 1
      verdict: 'Solid: no class. Powder and swarf: flammable'
      lead: The solid metal is not hazard-classed in the sources read. PubChem gives titanium a flammable-solid classification (H228), which applies to powder and swarf.
      points:
        - label: Solid metal
          line: Sheet, strip, plate, bar and tube are covered by the Smiths datasheet and the ATI page, which list no hazard classification.
        - label: Powder and swarf
          line: PubChem gives H228 (flammable solid) from aggregated reports, and reports 606 of 808 company reports as not meeting GHS hazard criteria. Treat powder and swarf as a fire hazard.
  why: Grade 3 is the commercially pure titanium with the highest minimum tensile strength of Grades 1 to 3 in ASTM B265 Table 1. It keeps the formability and weldability of the CP grades, with 18 % minimum elongation and a typical 25 % in the Smiths datasheet. It is chosen where CP titanium must be stronger than Grade 2 and corrosion resistance in oxidising, neutral and mildly reducing media is enough.
  uses:
    - where: Heat exchangers
      line: Alleima says the grade is typically used for matrix plates in shell and tube heat exchangers.
    - where: Aerospace sheet and plate
      line: United Performance Metals lists aerospace structures among its applications for Grade 3 sheet and coil to AMS 4900.
    - where: Architecture and industrial equipment
      line: Smiths lists architecture, automotive, chemical plant and marine industries among the typical applications for CP Grade 3.
  can_do:
    - label: Strength
      benchmark: ultimate_tensile_strength
      line: Minimum tensile strength 450 MPa and minimum 0.2 % yield strength 380 MPa for strip, sheet and plate (ASTM B265). Typical values in the Smiths datasheet are 593 MPa tensile and 462 MPa yield.
    - label: Ductility
      benchmark: elongation
      line: Minimum elongation 18 % (ASTM B265, 2 in or 50 mm gauge). Typical 25 % in the Smiths datasheet.
    - label: Stiffness
      benchmark: elastic_modulus
      line: Elastic modulus 103 GPa, typical (Smiths). The UPM datasheet prints 15.2 to 17.4 Msi.
    - label: Corrosion
      line: Smiths rates high corrosion resistance in oxidising, neutral and mildly reducing media, including chlorides.
    - label: Weldability
      line: Smiths rates weldability as excellent.
  compare: Grade 3 has the highest minimum tensile strength and yield strength of unalloyed grades 1 to 3 in ASTM B265 Table 1, at 450 MPa tensile and 380 MPa yield. The stronger alloy is [Ti-6Al-4V](/materials/ti-6al-4v), which is not a commercially pure grade.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Elastic modulus
      benchmark: elastic_modulus
    - label: Yield strength
      benchmark: yield_strength
  handling:
    - 'Welding: excellent weldability. Smiths specifies a welded bend radius of 3.0 times thickness at minimum.'
    - 'Bending: specified bend radius is 2.0 times thickness below 0.070 in and 2.5 times above it (Smiths). The ASTM B265 bend-test radii are the same.'
    - 'Fire: powder and swarf are a flammable-solid hazard (PubChem H228).'
  good_for:
    - Heat-exchanger matrix plates, where the grade is typically used (Alleima).
    - Forming and welding of sheet, strip and plate that needs more strength than Grade 2 (ASTM B265 Table 1; Smiths).
    - Aerospace sheet and coil to AMS 4900 (UPM, ATI).
  watch_out:
    - 'Lower strength than Ti-6Al-4V: 450 MPa minimum tensile (see the Ti-6Al-4V profile).'
    - No Grade 3 crevice or seawater test was found; the Titanium Industries page gives only general titanium statements.
    - Bending tighter than 2T (under 0.070 in) or 2.5T (0.070 to 0.187 in) is outside the ASTM bend-test radii.
    - Powder and swarf are a flammable-solid fire hazard (PubChem).
    - 'Composition limits differ between sources: Alleima prints lower Fe and O (nominal). ASTM B265 is used here.'
  verdict: CP titanium Grade 3 is the strongest of the commercially pure grades 1 to 3, with a 450 MPa minimum tensile strength and 18 % minimum elongation. It keeps good weldability and corrosion resistance in oxidising, neutral and mildly reducing media, including chlorides. It is not a structural alloy like Ti-6Al-4V, and the sources read give no Grade 3 crevice or seawater test.
composition:
  basis: weight percent, ASTM B265-08b Table 2, Grade 3 column
  source: astm-b265
  where: Table 2 Chemical Requirements, Grade 3 column
  limits:
    - element: O
      max: 0.35
    - element: Fe
      max: 0.3
    - element: C
      max: 0.08
    - element: 'N'
      max: 0.05
    - element: H
      max: 0.015
  note: ASTM B265-08b Table 2 gives these maxima. Smiths prints C max 0.1, O max 0.35 and H max 0.015 (sheet) or 0.0125 (bar). ATI prints N max 0.03 for plate, sheet and strip. Alleima prints lower nominal values (Fe 0.20, O 0.205, C 0.08, H 0.01, N 0.05). The ASTM values are used.
critical_lists: []
supply_note: Shares are computed by the assistant from the printed tonnage and the printed world total (USGS rounds its world totals), not printed by USGS.