spore: profile
id: titanium-grade-12
spore_version: 0.2
family: titanium-alloys
name: Titanium grade 12, Ti-0.3Mo-0.8Ni (UNS R53400)
abbreviation: Ti Gr 12
role: corrosion-resistant lean titanium alloy
category: metals
type: titanium
summary: |
  Titanium Grade 12, UNS R53400, is a lean titanium alloy with 0.2 to 0.4 % molybdenum and 0.6 to 0.9 % nickel. ASTM B265 sets its minimum tensile strength at 483 MPa and its minimum 0.2 % yield strength at 345 MPa, with 18 % minimum elongation for sheet and plate. The TIMETAL datasheet says it improves on unalloyed titanium, particularly for crevice corrosion in hot brines. The Alleima datasheet gives a density of 4.51 g/cm3, an elastic modulus of 103 GPa in tension, a melting point of 1660 °C and a beta transus of 890 °C.
best_for: Chemical process equipment and heat exchangers where corrosion resistance matters and the extra strength over unalloyed titanium is wanted (TIMETAL and Alleima datasheets)
weakest_at: 'Crevice attack still possible in hot brine: the TIMETAL datasheet shows an improvement over unalloyed titanium, not immunity. Its strength is well below Ti-6Al-4V.'
identity:
  formula: Titanium with 0.2 to 0.4 % molybdenum and 0.6 to 0.9 % nickel (nominal 0.3 Mo and 0.8 Ni), UNS R53400 (ASTM Grade 12)
  source: alleima-ti12
  where: Chemical composition (nominal) table, Mo and Ni rows; ASTM B265 Table 2 Grade 12 column
  designations:
    - system: UNS
      code: R53400
      source: alleima-ti12
      where: Standards list, UNS line
    - system: Name
      code: Grade 12
      source: alleima-ti12
      where: Standards list, ASTM Grade 12 line
    - system: Trade name
      code: TIMETAL Grade 12
      source: timet12
      where: Datasheet title, TIMETAL Grade 12 (ASTM Grade 12)
    - system: ASTM
      code: B265
      note: strip, sheet and plate
      source: astm-b265
      where: Title, B 265 - 08b; Table 2 Chemical Requirements, Grade 12 column
    - system: ASTM
      code: B337
      note: seamless and welded pipe
      source: alleima-ti12
      where: Tubing and pipe specifications list, ASTM B337 line
    - system: ASTM
      code: B338
      note: seamless and welded tube
      source: alleima-ti12
      where: Tubing and pipe specifications list, ASTM B338 line
    - system: ASME
      code: SB338
      note: seamless and welded tube
      source: alleima-ti12
      where: Tubing and pipe specifications list, ASME SB338 line
tags:
  environments: []
  stresses: []
  applications:
    - thermal-control
    - structures
properties:
  - benchmark: density
    label: Density
    value: 4.51
    unit: g/cm3
    scope: material
    conditions:
      form: not stated
      condition: not stated
    method: Printed as 4.51 g/cm3 (0.163 lb/in3) in the TIMETAL datasheet, Table 2 Physical Properties. The Alleima Grade 12 datasheet prints the same 4.51 g/cm3.
    status: ground
    source: timet12
    where: Table 2 Physical Properties, Density row
  - benchmark: elastic_modulus
    label: Elastic modulus (tension)
    value: 103
    unit: GPa
    scope: material
    conditions:
      loading: tension
      condition: not stated
    method: Printed as Tensile Modulus, Tension, 15 Msi and 103 GPa in the TIMETAL datasheet, Table 2. The Alleima datasheet prints Tension (E) 15.0 x 10^6 psi and 103 GPa.
    status: ground
    source: timet12
    where: Table 2 Physical Properties, Tensile Modulus Tension row
  - benchmark: melting_point
    label: Melting point
    value: 1660
    unit: °C
    scope: material
    conditions:
      printed_as: 3020 °F
      condition: not stated
    method: Printed as 3020 °F and 1660 °C in the Physical properties section of the Alleima Grade 12 datasheet. The Celsius value is used.
    status: ground
    source: alleima-ti12
    where: Physical properties, Melting point row
  - benchmark: beta_transus
    label: Beta transus
    value: 890
    unit: °C
    scope: material
    conditions:
      printed_as: 1634 F
      condition: not stated
    method: Printed as 1634F, 890°C in the Physical properties section of the Alleima Grade 12 datasheet. The Celsius value is used. beta_transus is a snake_case name (see gaps).
    status: ground
    source: alleima-ti12
    where: Physical properties, Beta transus row
  - benchmark: thermal_conductivity
    label: Thermal conductivity at room temperature
    value: 19.02
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: 24 °C (printed as 75 °F)
      unit_in_source: W/m.K
    method: Printed as 11 Btu/ft·h·°F and 19.02 W/m.K in Table 3 Selected Thermal Properties of the TIMETAL datasheet, 75 °F (24 °C) row, SI column.
    status: ground
    source: timet12
    where: Table 3 Selected Thermal Properties, Thermal Conductivity column, 75 °F (24 °C) row
  - benchmark: specific_heat
    label: Specific heat capacity at room temperature
    value: 544
    unit: J/(kg·K)
    scope: material
    conditions:
      temperature: 24 °C (printed as 75 °F)
      unit_in_source: J/kg
    method: Table 3 of the TIMETAL datasheet prints 0.13 Btu/lb.°F and (544) in the SI column, which the header labels (J/kg). The unit is written J/(kg·K) as the standard unit for specific heat capacity; the datasheet prints no K.
    status: ground
    source: timet12
    where: Table 3 Selected Thermal Properties, Specific Heat Capacity column, 75 °F (24 °C) row
  - benchmark: cte
    label: Coefficient of thermal expansion at room temperature
    value: 9.54
    unit: 10^-6/°C
    scope: material
    conditions:
      temperature: 24 °C (printed as 75 °F)
      unit_in_source: 10^-6/°C
    method: Printed as 5.3 x 10^-6 /°F and (9.54 x 10^-6/°C) at 75 °F (24 °C) in Table 3 of the TIMETAL datasheet. The Celsius value is used.
    status: ground
    source: timet12
    where: Table 3 Selected Thermal Properties, Coefficient of Thermal Expansion column, 75 °F (24 °C) row
  - benchmark: electrical_resistivity
    label: Electrical resistivity at room temperature
    value: 52
    unit: µΩ·cm
    scope: material
    conditions:
      temperature: 24 °C (printed as 75 °F)
      unit_in_source: µΩ.cm
    method: Printed as 52 µΩ.cm in the Electrical Resistivity column of Table 3 of the TIMETAL datasheet, 75 °F (24 °C) row.
    status: ground
    source: timet12
    where: Table 3 Selected Thermal Properties, Electrical Resistivity column, 75 °F (24 °C) row
  - benchmark: max_service_temp
    label: Maximum temperature approved under the ASME Boiler Code
    value: 600
    unit: °F
    scope: material
    conditions:
      basis: ASME Boiler Code approval statement, not a measured limit
    method: Printed as Grade 12 is approved by ASME Boiler Code for use up to 600°F in the introduction of the TIMETAL datasheet. It is an approval statement, not a test result.
    status: ground
    source: timet12
    where: Introduction paragraph, second sentence
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, minimum (strip, sheet and plate)
    value: 483
    bound: lower
    unit: MPa
    scope: material
    conditions:
      form: strip, sheet and plate (ASTM B265 product)
      condition: as specified for Grade 12 in ASTM B265-08b Table 1
      minimum: 'yes'
    method: Minimum in Table 1 (Tensile Requirements) of the ASTM B265-08b copy, Grade 12 row, with 70 ksi printed beside 483 MPa.
    status: ground
    source: astm-b265
    where: Table 1 Tensile Requirements, Grade 12 row, tensile strength min (ksi 70, MPa 483)
  - benchmark: yield_strength
    label: Yield strength, 0.2 % offset, minimum (strip, sheet and plate)
    value: 345
    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 12 row, with 50 ksi printed beside 345 MPa. No maximum is printed for Grade 12.
    status: ground
    source: astm-b265
    where: Table 1 Tensile Requirements, Grade 12 row, yield strength 0.2 % offset min (ksi 50, MPa 345)
  - 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 12 row.
    status: ground
    source: astm-b265
    where: Table 1 Tensile Requirements, Grade 12 row, elongation in 2 in. or 50 mm min %
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, minimum (seamless tube and pipe)
    value: 483
    bound: lower
    unit: MPa
    scope: material
    conditions:
      form: seamless tube and pipe (Alleima Ti Grade 12 product)
      condition: cold reduced or cold reduced and annealed, as supplied
      minimum: 'yes'
    method: Printed as Min 70 ksi and 483 MPa in the Mechanical properties table of the Alleima Grade 12 datasheet. The typical data row is not recorded (see gaps).
    status: ground
    source: alleima-ti12
    where: Mechanical properties, Min row, Ultimate Strength (ksi 70, MPa 483)
  - benchmark: yield_strength
    label: Yield strength, minimum (seamless tube and pipe)
    value: 345
    bound: lower
    unit: MPa
    scope: material
    conditions:
      form: seamless tube and pipe (Alleima Ti Grade 12 product)
      condition: cold reduced or cold reduced and annealed, as supplied
      minimum: 'yes'
    method: Printed as Min 50 ksi and 345 MPa in the same Alleima table.
    status: ground
    source: alleima-ti12
    where: Mechanical properties, Min row, Yield strength (ksi 50, MPa 345)
  - benchmark: elongation
    label: Elongation, minimum (seamless tube and pipe)
    value: 18
    bound: lower
    unit: '%'
    scope: material
    conditions:
      form: seamless tube and pipe (Alleima Ti Grade 12 product)
      gauge: 2 in
      minimum: 'yes'
    method: Printed as Elongation 2 in, Min 18 in the same Alleima table.
    status: ground
    source: alleima-ti12
    where: Mechanical properties, Min row, Elongation 2 in
corrosion:
  - environment: Hot brine, crevice corrosion (compared with unalloyed Grade 2)
    headline: Significant improvement over unalloyed titanium, particularly crevice corrosion in hot brines.
    effect: TIMETAL says Grade 12 shows significant improvement over unalloyed titanium, particularly crevice corrosion in hot brines. Its Figure 1 plots the effect of temperature and pH on crevice corrosion of Grade 2 against Grade 12 in saturated NaCl brine. The figure has no printed rate, so no numeric limit is recorded.
    rating: moderate
    conditions:
      basis: manufacturer statement and figure title; figure values not readable as text
      electrolyte: saturated NaCl brine (Figure 1)
    source: timet12
    where: Introduction paragraph; Figure 1 title
  - environment: Reducing and oxidizing environments
    headline: Excellent corrosion resistance in reducing and oxidizing environments.
    effect: Alleima says Grade 12 is characterized by excellent corrosion resistance in reducing and oxidizing environments, and is suitable for shell and tube heat exchangers in the chemical industries. The datasheet prints no test conditions.
    rating: low
    conditions:
      basis: manufacturer statement; no test conditions printed
    source: alleima-ti12
    where: Product description, first paragraph
risks:
  hazards:
    - text: PubChem aggregates GHS reports for titanium (CID 23963). Most reports say not classified (606 of 808). Of the 202 reports that give hazard codes, the ECHA notifications list H228 (flammable solid) and H250 (catches fire spontaneously if exposed to air), both under the signal word Danger. The record is for the element and does not separate bulk metal from powder or swarf.
      ghs:
        - 'H228: Flammable solid'
        - 'H250: Catches fire spontaneously if exposed to air'
      source: pubchem-ti
      where: Safety and Hazards, GHS Classification (CID 23963)
  failure_risks:
    - mode: Crevice corrosion in hot brine
      trigger: Tight crevices in hot brine
      consequence: Reduced compared with Grade 2 but not excluded; TIMETAL shows the effect in Figure 1 without a printed rate
      severity: moderate
      source: timet12
      where: Introduction paragraph; Figure 1 title
    - mode: Galling of the tube bore and springback in bending
      trigger: Bending thin-walled tube or using a tight radius without a well-lubricated mandrel
      consequence: Galling of the ID surface; springback about twice that of stainless steel
      severity: low
      source: alleima-ti12
      where: Fabrication, Bending section
    - mode: Fire from titanium powder or swarf
      trigger: Titanium powder or swarf in the workshop
      consequence: Flammable solid classification from PubChem aggregated reports (H228)
      severity: moderate
      source: pubchem-ti
      where: Safety and Hazards, GHS Classification (CID 23963)
  side_effects: []
  handling:
    - text: Welding is by manual or automatic TIG. Inert gas must shield both OD and ID of tube, the surface must be free of grease and oil, a low heat input is used, and no post-weld heat treatment is normally performed.
      source: alleima-ti12
      where: Weldability section
    - text: Bend with a well-lubricated mandrel on thin-walled tube to prevent galling of the ID. Allow for springback about twice that of stainless steel.
      source: alleima-ti12
      where: Fabrication, Bending section
    - text: 'Sheet minimum bend radius (D/T): 4 for thickness under 0.070 in and 5 for 0.070 to 0.187 in.'
      source: timet12
      where: Table 4 Minimum Mechanical Properties, Minimum Bend Radius column
    - text: 'Machining: low cutting speed, high feed, plenty of coolant, sharp tools, and never stop feeding while the tool is in contact.'
      source: alleima-ti12
      where: Fabrication, Machining and cutting section
  mitigations: []
uses:
  - application: thermal-control
    device: Shell and tube heat exchangers
    example: Alleima says Grade 12 is suitable for shell and tube heat exchangers and is typically used within the chemical industries.
    source: alleima-ti12
    where: Product description, first paragraph
  - application: structures
    device: ASME Boiler Code pressure parts
    example: TIMETAL says Grade 12 is approved by the ASME Boiler Code for use up to 600 °F.
    source: timet12
    where: Introduction paragraph
supply:
  - subject: Titanium sponge (feedstock for titanium mill products)
    abundance: Not printed in the USGS 2026 titanium summary read for this profile. It refers to the Titanium Mineral Concentrates chapter for resources.
    producers:
      - country: China
        share_percent: 70.3
        year: 2025
        basis: 'computed: 260,000 t of 370,000 t world sponge (USGS World Sponge Metal Production table, 2025e)'
      - 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 did not produce titanium sponge in 2025; the last domestic sponge plant closed in 2024. U.S. imports of titanium sponge were an estimated 44,000 tons in 2025.
    source: usgs-ti-2026
    where: Domestic Production and Use; Events, Trends, and Issues; World Sponge Metal Production table
media: []
documents:
  - 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: TIMETAL Grade 12 datasheet (TIMET)
    type: datasheet
    url: https://www.timet.com/documents/datasheets/cp-grades/timetal-grade-12.pdf
  - title: Alleima Ti Grade 12, 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-12
    year: 2025
  - 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
gaps:
  - 'Hardness, fatigue, Poisson''s ratio, shear and bulk modulus, specific heat of the Alleima tube (not printed there), and toughness: no Grade 12 values in the sources read in this run.'
  - 'Alleima typical tensile data (printed as 573, 421 and 36 with no unit row in the extracted text) is not recorded: the units cannot be read with certainty.'
  - Alleima thermal conductivity table prints 18.1 W/mK at 23 °C with a comma decimal (18,1). It conflicts with the TIMETAL value of 19.02 W/(m·K) at 24 °C, so only the TIMETAL value is recorded.
  - 'Oxygen: Alleima prints nominal maximum 0.18 %, ASTM B265 Table 2 prints 0.25 % maximum, and TIMETAL prints 0.25 % maximum (0.12 nominal). The ASTM value is used for the composition.'
  - 'Organic acid corrosion table (TIMETAL Table 5): the numbers are printed with no unit, so none are recorded.'
  - 'Reduction of area (TIMETAL Table 4, 25 for bar, billet and forgings): the column prints no unit, so it is not recorded.'
  - 'Seawater and chloride data for Grade 12: none found in the sources read. The ASTM STP 487 and Brookhaven crevice papers were found by search but not read in this run (the NRC PDF link returned an HTML page).'
  - 'Designations: EN, DIN, JIS, AISI and ISO codes for Grade 12 are printed on none of the pages read in this run.'
  - 'Edition: the ASTM B265 copy is the 08b edition (its header says B 265 - 08b). The current edition should be checked before specifying.'
  - Atomic weights of molybdenum and nickel were not fetched, so the recipe parts carry share limits only.
  - 'Critical-mineral lists: the USGS 2026 titanium summary read for this profile does not list them, and the EU and USGS critical lists were not fetched.'
  - 'Crustal abundance of titanium: not printed in the USGS 2026 titanium summary read for this profile.'
  - Beta transus is a snake_case name (not in spores/property-canon.yaml). Reduction of area is left out (see above).
  - 'Sources: six were read in this run. Search returned mainly aggregator pages (matmatch, mfgrobots, totalmateria, azom); their numbers were not used. The eight-source target was not reached from primary pages.'
sources:
  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
  timet12:
    title: TIMETAL Grade 12 datasheet (TIMET)
    id: TIMET
    url: https://www.timet.com/documents/datasheets/cp-grades/timetal-grade-12.pdf
    kind: datasheet
    license: supplier datasheet, cited not reproduced
  alleima-ti12:
    title: Alleima Ti Grade 12, seamless tube and pipe datasheet (updated 2025-05-09)
    id: Alleima
    url: https://alleima.com/en/technical-center/material-datasheets/tube-and-pipe-seamless/alleima-ti-grade-12
    year: 2025
    kind: datasheet
    license: supplier datasheet, 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
  wiki-ti-alloy:
    title: Titanium alloy (Wikipedia)
    id: Wikipedia, Titanium alloy
    url: https://en.wikipedia.org/wiki/Titanium_alloy
    year: 2026
    kind: web
    license: CC BY-SA 4.0
license: CC-BY-4.0
updated: '2026-10-26'
review:
  status: draft
  method: assistant
  checked_values: 15
  unreachable: 1
  caveats: 3
  note: 'Written 2026-10-26 by an assistant from pages read in this run: ASTM B265-08b copy (Tables 1 and 2), TIMETAL Grade 12 datasheet (Tables 1 to 4), Alleima Ti Grade 12 datasheet, USGS MCS 2026 titanium, PubChem CID 23963. Wikipedia used for the composition note only. The NRC Brookhaven PDF was not readable.'
story:
  recipe:
    line: 'Unalloyed titanium with molybdenum and nickel added at low levels: 0.2 to 0.4 % Mo and 0.6 to 0.9 % Ni in ASTM B265 Table 2, Grade 12 column. Impurity limits are placed on O, Fe, C, N and H, with titanium the balance. Wikipedia describes the grade as containing 0.3 % molybdenum and 0.8 % nickel. 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: astm-b265
        where: Table 2 Chemical Requirements, Titanium balance row
      - name: Molybdenum
        symbol: Mo
        share_low: 0.2
        share_high: 0.4
        share_note: 0.2 to 0.4 %
        role: Alloying addition. Its specific role is not stated in the sources read.
        source: astm-b265
        where: Table 2 Chemical Requirements, Molybdenum row, Grade 12 column
      - name: Nickel
        symbol: Ni
        share_low: 0.6
        share_high: 0.9
        share_note: 0.6 to 0.9 %
        role: Alloying addition. Its specific role is not stated in the sources read.
        source: astm-b265
        where: Table 2 Chemical Requirements, Nickel row, Grade 12 column
      - name: Oxygen
        symbol: O
        share_high: 0.25
        share_note: maximum 0.25 %
        role: Interstitial impurity with a maximum limit.
        source: astm-b265
        where: Table 2 Chemical Requirements, Oxygen max, Grade 12 column
      - name: Iron
        symbol: Fe
        share_high: 0.3
        share_note: maximum 0.30 %
        role: Impurity with a maximum limit.
        source: astm-b265
        where: Table 2 Chemical Requirements, Iron max, Grade 12 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 12 column
      - name: Nitrogen
        symbol: 'N'
        share_high: 0.03
        share_note: maximum 0.03 %
        role: Interstitial impurity with a maximum limit.
        source: astm-b265
        where: Table 2 Chemical Requirements, Nitrogen max, Grade 12 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 12 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 here. PubChem gives titanium H228 (flammable solid) and H250 (pyrophoric) from aggregated reports, which apply to powder and swarf.
      points:
        - label: Solid metal
          line: Sheet, plate, bar and tube are covered by the TIMETAL and Alleima datasheets, which carry no hazard classification.
        - label: Powder and swarf
          line: PubChem gives H228 and H250 for the element from ECHA notifications (202 of 808 company reports give hazard codes). Treat powder and swarf as a fire hazard.
  why: TIMETAL describes Grade 12 as a lean titanium alloy with excellent corrosion resistance and higher strength than ASTM Grade 2. Alleima says it has excellent corrosion resistance in reducing and oxidizing environments. It is chosen where corrosion resistance matters and extra strength over unalloyed titanium is wanted.
  uses:
    - where: Shell and tube heat exchangers
      line: Alleima says Grade 12 is suitable for shell and tube heat exchangers and is typically used in the chemical industries.
    - where: ASME pressure parts
      line: TIMETAL says Grade 12 is approved by the ASME Boiler Code for use up to 600 °F.
  can_do:
    - label: Strength
      benchmark: ultimate_tensile_strength
      line: Minimum tensile strength 483 MPa and minimum 0.2 % yield strength 345 MPa for strip, sheet and plate (ASTM B265). The same minimums are printed for seamless tube by Alleima.
    - label: Ductility
      benchmark: elongation
      line: Minimum elongation 18 % for strip, sheet and plate (ASTM B265) and for seamless tube (Alleima).
    - label: Stiffness
      benchmark: elastic_modulus
      line: Elastic modulus 103 GPa in tension (TIMETAL and Alleima).
    - label: Corrosion
      line: Improved crevice resistance in hot brine over unalloyed titanium (TIMETAL). Excellent resistance in reducing and oxidizing environments (Alleima).
  compare: Grade 12 is an alloyed grade with higher strength than unalloyed Grade 2 and Grade 7 (TIMETAL), and it keeps the low density of titanium at 4.51 g/cm3. Its tensile modulus is 103 GPa, roughly half that of steel alloys (Alleima).
  compare_rows:
    - scope: material
      label: Density
      benchmark: density
    - scope: material
      label: Elastic modulus
      benchmark: elastic_modulus
    - scope: material
      label: Yield strength
      benchmark: yield_strength
  handling:
    - 'Welding: manual or automatic TIG. Shield both OD and ID of tube with inert gas, keep the surface free of grease and oil, use a low heat input, and no post-weld heat treatment is normally needed (Alleima).'
    - 'Bending: use a well-lubricated mandrel on thin-walled tube and allow for springback about twice that of stainless steel (Alleima). TIMETAL prints a minimum bend radius (D/T) of 4 for sheet under 0.070 in thick and 5 for 0.070 to 0.187 in.'
    - 'Machining: low cutting speed, high feed, plenty of coolant, sharp tools, and never stop feeding while the tool is in contact (Alleima).'
  good_for:
    - Chemical process heat exchangers and shell and tube equipment (Alleima).
    - Pressure parts up to 600 °F under the ASME Boiler Code (TIMETAL).
    - Hot brine and chloride service where unalloyed titanium is too weak or too prone to crevice attack (TIMETAL).
  watch_out:
    - 'Crevice attack in hot brine is improved, not excluded: TIMETAL shows the effect in Figure 1 without a printed rate.'
    - 'Lower strength than Ti-6Al-4V: the minimum tensile strength here is 483 MPa.'
    - Springback is about twice that of stainless steel in bending (Alleima).
    - Powder and swarf are a flammable-solid fire hazard (PubChem).
  verdict: Grade 12 is a corrosion-resistant titanium alloy with a higher minimum strength than unalloyed grades and improved crevice resistance in hot brine. It is not a structural alloy like Ti-6Al-4V, and the sources read here give no rate data for seawater or other chlorides.
composition:
  basis: weight percent, ASTM B265-08b Table 2, Grade 12 column
  source: astm-b265
  where: Table 2 Chemical Requirements, Grade 12 column
  limits:
    - element: Mo
      min: 0.2
      max: 0.4
    - element: Ni
      min: 0.6
      max: 0.9
    - element: O
      max: 0.25
    - element: Fe
      max: 0.3
    - element: C
      max: 0.08
    - element: 'N'
      max: 0.03
    - element: H
      max: 0.015
  note: ASTM B265-08b Table 2 prints Mo 0.2 to 0.4, Ni 0.6 to 0.9, O max 0.25, Fe max 0.30, C max 0.08, N max 0.03 and H max 0.015 for Grade 12. Alleima prints O max 0.18 (nominal). The ASTM values are used.
critical_lists: []
supply_note: Shares are computed from the printed tonnage and the printed world total (USGS rounds its world totals), not printed by USGS. The same USGS sponge table is used as for Grade 2 because no Grade 12 supply data exist.