Hastelloy B-2 Ni-Mo

spore: profile
id: hastelloy-b2
spore_version: 0.2
family: nickel-alloys
name: Hastelloy B-2
abbreviation: Ni-Mo
role: corrosion-resistant alloy for reducing acids
category: metals
type: nickel-superalloys
summary: |
  Hastelloy B-2 (UNS N10665, W. Nr./EN 2.4617) is a nickel-molybdenum alloy made for reducing acids. The Haynes safety data sheet gives its nominal composition as 69 % nickel and 28 % molybdenum. Rolled Alloys gives a minimum specified tensile strength of 110 ksi and a minimum specified yield strength of 51 ksi for sheet and plate. In Haynes's table of boiling-acid corrosion, B-2 corrodes at 15 mpy in boiling 20 % hydrochloric acid and at 1.0 mpy in boiling 50 % sulfuric acid. It has no significant chromium, so it is not used in oxidising media.
best_for: 'Reducing acids at high concentration and temperature: 15 mpy in boiling 20 % hydrochloric acid and 1.0 mpy in boiling 50 % sulfuric acid (Haynes)'
weakest_at: Oxidising media, oxidising salts, wet chlorine and hypochlorite bleach (no chromium); loss of ductility in the 1000 to 1600 °F range (Rolled Alloys)
identity:
  formula: Ni-Mo alloy; nominal composition in the Haynes SDS is nickel 69 % and molybdenum 28 % by weight, with low chromium, iron, manganese, cobalt, silicon and carbon
  source: haynes-sds
  where: Section 3 composition table (page 5 of 16), B-2 alloy column; Rolled Alloys chemical composition table for the specified ranges
  designations:
    - system: UNS
      code: N10665
      source: rolled-b2
      where: 'Specifications line, UNS: N10665'
    - system: EN
      code: '2.4617'
      source: rolled-b2
      where: 'Specifications line, W. Nr./EN: 2.4617'
    - system: ASTM
      code: B333
      source: rolled-b2
      where: 'Specifications line, ASTM: B 333'
    - system: ASTM
      code: B335
      source: rolled-b2
      where: 'Specifications line, ASTM: B 335'
    - system: ASTM
      code: B619
      source: rolled-b2
      where: 'Specifications line, ASTM: B 619'
    - system: ASTM
      code: B622
      source: rolled-b2
      where: 'Specifications line, ASTM: B 622'
    - system: ASTM
      code: B626
      source: rolled-b2
      where: 'Specifications line, ASTM: B 626'
    - system: ASTM
      code: B366
      source: rolled-b2
      where: 'Specifications line, ASTM: B 366'
tags:
  environments: []
  stresses: []
  applications:
    - structures
properties:
  - benchmark: density
    label: Density
    value: 0.333
    unit: lb/in3
    scope: material
    conditions:
      basis: printed in the Physical Properties block of the Rolled Alloys datasheet; no metric value is printed on that page
      temperature: not stated
    method: Value printed in a distributor datasheet (Rolled Alloys Bulletin 303U)
    status: ground
    source: rolled-b2
    where: Physical Properties block, Density line
  - benchmark: melting_point
    label: Melting point (approximate)
    value: 2425
    unit: °F
    scope: material
    conditions:
      basis: printed with a tilde (approximate) in the Haynes SDS composition table
      pressure: not stated
    method: Approximate value printed in the manufacturer's safety data sheet
    status: ground
    source: haynes-sds
    where: Composition table (page 5 of 16), Melting Point (° F) row, B-2 alloy column
  - benchmark: electrical_resistivity
    label: Electrical resistivity
    value: 824
    unit: Ohm-circ mil/ft
    scope: material
    conditions:
      temperature: room temperature, as the datasheet lists the property without a temperature
      form: not stated
    method: Value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Physical Properties block, Electrical Resistivity line
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 212 °F
    value: 7.1
    unit: Btu • ft/ft2 • hr • °F
    scope: material
    conditions:
      temperature: 212 °F (the column heading as printed)
      basis: value in the Thermal Conductivity row of the table
    method: Value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Physical Properties table, Thermal Conductivity row, 212 column
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 932 °F
    value: 10
    unit: Btu • ft/ft2 • hr • °F
    scope: material
    conditions:
      temperature: 932 °F (the column heading as printed)
      basis: value in the Thermal Conductivity row of the table
    method: Value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Physical Properties table, Thermal Conductivity row, 932 column
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, typical, sheet and plate
    value: 130
    unit: ksi
    scope: material
    conditions:
      form: sheet and plate (average tensile data heading)
      basis: typical value
      temper: not stated
      temperature: not stated
    method: Typical value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Mechanical Properties block, Ultimate Tensile Strength, Typical column
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, minimum specified, sheet and plate
    value: 110
    bound: lower
    unit: ksi
    scope: material
    conditions:
      form: sheet and plate (average tensile data heading)
      basis: minimum specified
      temper: not stated
      temperature: not stated
    method: Minimum specified value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Mechanical Properties block, Ultimate Tensile Strength, Minimum Specified column
  - benchmark: yield_strength
    label: 0.2 % yield strength, typical, sheet and plate
    value: 59
    unit: ksi
    scope: material
    conditions:
      form: sheet and plate (average tensile data heading)
      basis: typical value, 0.2 % offset
      temper: not stated
      temperature: not stated
    method: Typical value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Mechanical Properties block, 0.2% Yield Strength, Typical column
  - benchmark: yield_strength
    label: 0.2 % yield strength, minimum specified, sheet and plate
    value: 51
    bound: lower
    unit: ksi
    scope: material
    conditions:
      form: sheet and plate (average tensile data heading)
      basis: minimum specified, 0.2 % offset
      temper: not stated
      temperature: not stated
    method: Minimum specified value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Mechanical Properties block, 0.2% Yield Strength, Minimum Specified column
  - benchmark: elongation
    label: Elongation, typical, sheet and plate
    value: 60
    unit: '%'
    scope: material
    conditions:
      form: sheet and plate (average tensile data heading)
      basis: typical value
      temper: not stated
    method: Typical value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Mechanical Properties block, Elongation, Typical column
  - benchmark: elongation
    label: Elongation, minimum specified, sheet and plate
    value: 40
    bound: lower
    unit: '%'
    scope: material
    conditions:
      form: sheet and plate (average tensile data heading)
      basis: minimum specified
      temper: not stated
    method: Minimum specified value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Mechanical Properties block, Elongation, Minimum Specified column
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, minimum, metric listing
    value: 760
    bound: lower
    unit: MPa
    scope: material
    conditions:
      basis: minimum value in the Mechanical Properties table of a supplier listing; the listing does not state the form or temper
      temperature: not stated
    method: Minimum value printed in a supplier table (Tachart)
    status: ground
    source: tachart-b2
    where: Mechanical Properties table, Ultimate Tensile Strength (UTS) row, Min column
  - benchmark: yield_strength
    label: 0.2 % proof stress, minimum, metric listing
    value: 350
    bound: lower
    unit: MPa
    scope: material
    conditions:
      basis: minimum value in the Mechanical Properties table of a supplier listing; the listing does not state the form or temper
      measure: 0.2 % proof stress
    method: Minimum value printed in a supplier table (Tachart)
    status: ground
    source: tachart-b2
    where: Mechanical Properties table, 0.2% Proof Stress row, Min column
  - benchmark: hardness_rockwell_b
    label: Hardness, typical, sheet and plate
    value: 94
    value_high: 98
    bound: range
    unit: HRB
    scope: material
    conditions:
      form: sheet and plate
      basis: typical value
      test: Rockwell B (the unit as printed)
    method: Typical range printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Mechanical Properties block, Hardness MAX row, Typical column
  - benchmark: hardness_rockwell_b
    label: Hardness, maximum specified, sheet and plate
    value: 100
    bound: upper
    unit: HRB
    scope: material
    conditions:
      form: sheet and plate
      basis: maximum specified
      test: Rockwell B (the unit as printed)
    method: Maximum specified value printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Mechanical Properties block, Hardness MAX row, Minimum Specified column
  - benchmark: phase_formation_temperature
    label: Temperature at which Ni4Mo forms rapidly in B-2
    value: 750
    unit: °C
    scope: material
    conditions:
      basis: stated as around 750°C in a Haynes brochure written about its B-3 alloy; the brochure says B-2 suffers rapid formation of Ni4Mo at that temperature
      time: rapid, no time given for B-2
    method: Approximate temperature stated in a manufacturer brochure
    status: ground
    source: haynes-b3-brochure
    where: Page 2 text, paragraph on B-3 versus its predecessor B-2 (the brochure's time-temperature-transformation comparison)
  - benchmark: molybdenum_content
    label: Molybdenum content, specified range
    value: 26
    value_high: 30
    bound: range
    unit: '%'
    scope: material
    conditions:
      basis: specified minimum and maximum, weight percent
    method: Specified range printed in a distributor datasheet
    status: ground
    source: rolled-b2
    where: Chemical Composition table, Mo row, MIN and MAX columns
  - benchmark: molybdenum_content
    label: Molybdenum content, nominal
    value: 28
    unit: '%'
    scope: material
    conditions:
      basis: nominal composition, weight percent, B-2 alloy column
    method: Nominal value printed in the manufacturer's safety data sheet
    status: ground
    source: haynes-sds
    where: Composition table (page 5 of 16), Molybdenum (Mo) row, B-2 alloy column
  - benchmark: nickel_content
    label: Nickel content, nominal
    value: 69
    unit: '%'
    scope: material
    conditions:
      basis: nominal composition, weight percent, B-2 alloy column
    method: Nominal value printed in the manufacturer's safety data sheet
    status: ground
    source: haynes-sds
    where: Composition table (page 5 of 16), Nickel (Ni) row, B-2 alloy column
  - benchmark: uniform_corrosion_rate
    label: Uniform corrosion, boiling 20 % hydrochloric acid
    value: 15
    unit: mpy
    scope: material
    conditions:
      environment: 20 % hydrochloric acid at boiling
      basis: average corrosion rate per year, printed in mils (mpy) by Haynes
    method: Average corrosion rate printed in a manufacturer table (Haynes Alloy at a Glance, H-2101E)
    status: ground
    source: haynes-glance
    where: Uniform Corrosion Resistance in Boiling Acids table, 20% Hydrochloric Acid row, B-2 column
  - benchmark: uniform_corrosion_rate
    label: Uniform corrosion, boiling 50 % sulfuric acid
    value: 1
    unit: mpy
    scope: material
    conditions:
      environment: 50 % sulfuric acid at boiling
      basis: average corrosion rate per year, printed in mils (mpy) by Haynes
    method: Average corrosion rate printed in a manufacturer table (Haynes Alloy at a Glance, H-2101E)
    status: ground
    source: haynes-glance
    where: Uniform Corrosion Resistance in Boiling Acids table, 50% Sulfuric Acid row, B-2 column
  - benchmark: uniform_corrosion_rate
    label: Uniform corrosion, boiling 50 % acetic acid
    value: 0.4
    unit: mpy
    scope: material
    conditions:
      environment: 50 % acetic acid at boiling
      basis: average corrosion rate per year, printed in mils (mpy) by Haynes
    method: Average corrosion rate printed in a manufacturer table (Haynes Alloy at a Glance, H-2101E)
    status: ground
    source: haynes-glance
    where: Uniform Corrosion Resistance in Boiling Acids table, 50% Acetic Acid row, B-2 column
  - benchmark: uniform_corrosion_rate
    label: Uniform corrosion, boiling 50-55 % phosphoric acid
    value: 6
    unit: mpy
    scope: material
    conditions:
      environment: 50-55 % phosphoric acid at boiling
      basis: average corrosion rate per year, printed in mils (mpy) by Haynes
    method: Average corrosion rate printed in a manufacturer table (Haynes Alloy at a Glance, H-2101E)
    status: ground
    source: haynes-glance
    where: Uniform Corrosion Resistance in Boiling Acids table, 50-55% Phosphoric Acid row, B-2 column
  - benchmark: time_to_intergranular_cracking
    label: Time to intergranular cracking, boiling 60 % sulfuric acid, after annealing plus 1 h at 700 °C
    value: 3
    unit: hours
    scope: material
    conditions:
      environment: boiling 60 % sulfuric acid, U-bend specimens (ASTM G-30 stress method)
      treatment: annealed plus 1 hour at 700 °C
      test_duration: 1,008 hours maximum in the table
    method: Time to cracking printed in a manufacturer table
    status: ground
    source: haynes-glance
    where: Stress Corrosion Cracking Tests table, B-2 entry (Intergranular cracking, 3 hours)
corrosion:
  - environment: Boiling 20 % hydrochloric acid
    headline: Boiling 20 % hydrochloric acid gives B-2 an average corrosion rate of 15 mpy in Haynes's table.
    effect: Haynes's Alloy at a Glance gives 15 mpy for B-2 in 20 % hydrochloric acid at boiling. The same table gives B-3 a lower rate, and gives far higher rates for 316L and Monel in the same test.
    rating: moderate
    conditions:
      basis: average corrosion rate per year from the manufacturer's table; test method not stated on the page
      concentration: 20 %
      temperature: boiling
    source: haynes-glance
    where: Uniform Corrosion Resistance in Boiling Acids table, 20% Hydrochloric Acid row
  - environment: Boiling 50 % sulfuric acid
    headline: Boiling 50 % sulfuric acid gives B-2 an average corrosion rate of 1.0 mpy in Haynes's table.
    effect: Haynes's table gives 1.0 mpy for B-2 and 1.1 mpy for B-3 in 50 % sulfuric acid at boiling. The same table gives much higher rates for 316L and Monel.
    rating: low
    conditions:
      basis: average corrosion rate per year from the manufacturer's table
      concentration: 50 %
      temperature: boiling
    source: haynes-glance
    where: Uniform Corrosion Resistance in Boiling Acids table, 50% Sulfuric Acid row
  - environment: Boiling 60 % sulfuric acid after annealing plus 1 h at 700 °C
    headline: After annealing plus 1 hour at 700 °C, B-2 cracks intergranularly in boiling 60 % sulfuric acid.
    effect: Haynes's U-bend test (ASTM G-30 stress method) shows intergranular cracking for B-2 after 3 hours with that heat treatment. The same table shows B-3 with "No cracking, 24 hours" under the same treatment.
    rating: severe
    conditions:
      specimen: U-bend, ASTM G-30 stress method
      treatment: annealed plus 1 hour at 700 °C
      environment: boiling 60 % sulfuric acid
    source: haynes-glance
    where: Stress Corrosion Cracking Tests table, B-2 entry; B-3 entry for comparison
  - environment: Oxidising media, oxidising salts, wet chlorine gas and hypochlorite bleach
    headline: B-2 should not be used in oxidising media, and it does not withstand wet chlorine or hypochlorite bleach.
    effect: Rolled Alloys says B-2 contains no significant chromium addition, so it should NOT be used in oxidizing media or in presence of oxidizing salts such as ferric or cupric salts, and it does not withstand wet chlorine gas or hypochlorite bleach. No rate is given.
    rating: severe
    conditions:
      basis: manufacturer statement, no rate given
    source: rolled-b2
    where: Data sheet, first paragraph
  - environment: Exposure in the 1000 to 1600 °F range
    headline: B-2 should not be exposed in the 1000 to 1600 °F range because of loss of ductility.
    effect: Rolled Alloys says B-2 should not be exposed to temperatures in the 1000 - 1600°F range because of severe loss of ductility. In a vacuum it may be used from 1600°F to substantially higher temperatures.
    rating: moderate
    conditions:
      basis: manufacturer statement, no test data printed
    source: rolled-b2-page
    where: Product page, usage notes
risks:
  hazards:
    - text: The Haynes SDS for the alloy group gives B-2 the GHS codes H350 (may cause cancer, Danger), H317 (allergic skin reaction, Warning), H334 (allergy or asthma symptoms or breathing difficulties if inhaled, Danger), H315 (skin irritation, Warning), H332 (harmful if inhaled, Warning) and H302 (harmful if swallowed, Warning). The SDS says the health hazards 'do not apply under normal handling and use of these products in solid form'.
      ghs:
        - H350
        - H317
        - H334
        - H315
        - H332
        - H302
      source: haynes-sds
      where: Section 2, GHS hazard classification table; section 2 opening paragraph
    - text: For nickel metal and other compounds (as Ni), NIOSH gives the recommended exposure limit as 'Ca TWA 0.015 mg/m3' and the IDLH as 'Ca [10 mg/m3 (as Ni)]'. These limits apply to airborne nickel dust or fume, not to the solid alloy.
      ghs: []
      source: niosh-npg-ni
      where: Exposure Limits, NIOSH REL and IDLH rows
  failure_risks:
    - mode: Loss of ductility in the 1000 to 1600 °F range
      trigger: Exposure to temperatures in the 1000 - 1600°F range, as Rolled Alloys warns
      consequence: Severe loss of ductility, per the Rolled Alloys datasheet
      severity: high
      source: rolled-b2-page
      where: Usage notes
    - mode: Intergranular cracking after annealing plus 1 h at 700 °C
      trigger: Boiling 60% H2SO4 (U-bend stress test) after annealing plus 1 hour at 700 °C
      consequence: Intergranular cracking in 3 hours, per the Haynes Alloy at a Glance table
      severity: high
      source: haynes-glance
      where: Stress Corrosion Cracking Tests table, B-2 entry
    - mode: Attack by oxidising media and oxidising salts
      trigger: Oxidising media, ferric or cupric salts, wet chlorine gas or hypochlorite bleach
      consequence: The Rolled Alloys datasheet says B-2 should not be used in oxidizing media or in the presence of oxidizing salts; no rate is printed
      severity: high
      source: rolled-b2
      where: Data sheet, first paragraph
  side_effects:
    - text: Haynes says the Ni4Mo phase, which forms rapidly in B-2 at around 750°C, 'affects ductility, and reduces resistance to stress corrosion cracking'.
      affects: Ductility and stress corrosion cracking resistance of welds and heat-treated parts
      source: haynes-b3-brochure
      where: Page 2 text on Ni4Mo (the brochure is written for B-3 and describes B-2 as its predecessor)
  handling:
    - text: The Haynes SDS says cutting, grinding and similar work can produce dust or particulate with the component elements, which carry the health hazards listed in section 2.
      source: haynes-sds
      where: Section 2 opening paragraph
    - text: If the alloy is welded or melted, the Haynes Wire Company SDS for welding products (HW-7031) also applies, according to the Haynes SDS.
      source: haynes-sds
      where: Section 2 opening paragraph
  mitigations: []
uses:
  - application: structures
    device: Chemical plant equipment for reducing acids
    example: Rolled Alloys lists 'Methyl methacrylate production with hot 98% H2SO4' and 'Acetic acid production, initial phase in presence of iodide catalyst' among the applications of B-2.
    source: rolled-b2-page
    where: Applications list on the product page
  - application: structures
    device: Bolting in hydrochloric acid service
    example: Tachart lists bolting as a use and says the alloy is 'Commonly used for its high corrosion resistance and high temperature strength in hydrochloric acid and other strongly reducing chemical environments.'
    source: tachart-b2
    where: Uses section of the page
  - application: structures
    device: Equipment exposed to hydrochloric acid
    example: Rolled Alloys says B-2 'Resists hydrochloric acid at all concentrations and temperatures' and 'Withstands wet HCl gas, sulfuric, acetic and phosphoric acids'.
    source: rolled-b2-page
    where: Features list on the product page
supply:
  - subject: Nickel
    producers:
      - country: Indonesia
        share_percent: 66.7
        year: 2025
      - country: Philippines
        share_percent: 6.9
        year: 2025
      - country: Russia
        share_percent: 5.1
        year: 2025
      - country: Canada
        share_percent: 3.6
        year: 2025
      - country: New Caledonia
        share_percent: 3.6
        year: 2025
    critical_lists:
      - list: USGS 2025 List of Critical Minerals (Nickel, used to make high-strength steel, and rechargeable batteries)
        listed: true
    recycling: 'USGS: nickel recovered from scrap accounted for approximately 60% of apparent consumption in 2025, and most secondary nickel is stainless-steel scrap.'
    substitutes:
      - 'USGS: ''Titanium alloys can substitute for nickel or nickel-base alloys in corrosive environments.'''
    source: usgs-mcs2026-nickel
    where: World Mine Production and Reserves table, 2025e column (world total 3,900,000 t of nickel; shares calculated by Space Mushroom from the country values); Recycling; Substitutes
  - subject: Molybdenum
    producers:
      - country: China
        share_percent: 37.3
        year: 2025
      - country: Chile
        share_percent: 16.2
        year: 2025
      - country: United States
        share_percent: 15.4
        year: 2025
      - country: Peru
        share_percent: 15
        year: 2025
      - country: Mexico
        share_percent: 6.5
        year: 2025
    critical_lists:
      - list: USGS 2025 List of Critical Minerals (molybdenum not on the list)
        listed: false
    recycling: 'USGS: molybdenum recycled as part of new and old steel and other scrap may be as much as 30% of the apparent supply, and superalloy scrap is recycled.'
    substitutes:
      - 'USGS: ''There is little substitution for molybdenum in its major application in steels and cast irons.'''
    source: usgs-mcs2026-molybdenum
    where: World Mine Production and Reserves table, 2025e column (world total 260,000 t of molybdenum; shares calculated by Space Mushroom from the country values); Recycling; Substitutes
documents:
  - title: Rolled Alloys datasheet, HASTELLOY B-2, Bulletin No. 303U (2011)
    type: datasheet
    url: https://www.rolledalloys.ca/wp-content/uploads/HASTELLOY-B-2_Datasheet-rolled-alloys.pdf
    year: 2011
  - title: Haynes International safety data sheet H2071-10, Corrosion-Resistant and High-Temperature Alloys (copy hosted by General Air)
    type: sds
    url: https://amp.generalair.com/MsdsDocs/WWH207110S.pdf
    year: 2020
  - title: Haynes International Alloy at a Glance, H-2101E (Hastelloy B-3 with B-2 comparison data)
    type: datasheet
    url: https://haynesintl.com/wp-content/uploads/2023/09/alloy-at-glance-b-3.pdf
    year: 2020
  - title: 'USGS Mineral Commodity Summaries 2026: Nickel'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
    year: 2026
  - title: 'USGS Mineral Commodity Summaries 2026: Molybdenum'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-molybdenum.pdf
    year: 2026
  - title: 'NIOSH Pocket Guide to Chemical Hazards: Nickel metal and other compounds (as Ni)'
    type: database
    url: https://www.cdc.gov/niosh/npg/npgd0445.html
gaps:
  - No melting range from a Haynes or Rolled Alloys B-2 datasheet was found; only the approximate melting point of about 2425 °F in the Haynes SDS composition table is recorded.
  - Elastic modulus, specific heat and thermal expansion of B-2 were not recorded. The Rolled Alloys expansion row prints its exponent only in the column heading (x 10 -6), so no value was entered.
  - The Haynes B-2 product page and the High Performance Alloys datasheet were not reachable (HTTP 404, 403 and 503 responses); values rest on the Rolled Alloys datasheet, the Rolled Alloys product page, Tachart, and the Haynes SDS and Alloy at a Glance.
  - Rolled Alloys strength values are average tensile data for sheet and plate, and the temper is not stated. The Tachart minimum values (760 MPa and 350 MPa) do not state form or temper either.
  - Corrosion rates for B-2 are only the uniform rates in boiling acids printed in the Haynes Alloy at a Glance table; no mm/y table for B-2 and no weld corrosion data for B-2 were found (the Haynes weld table belongs to B-3).
  - No stress corrosion cracking or corrosion data for B-2 in aerated or unboiled acids, and no corrosion data for B-2 in chloride solutions, were found.
  - 'No space-related data were found for B-2: no vacuum outgassing, radiation, atomic oxygen or flight result. tags.environments is empty for that reason.'
  - No manufacturing route (melting practice, cold work limits, heat treatment) for B-2 was found in the sources opened.
  - 'Designations: the Tachart aliases NiMo28 and ND30M, and the ASME codes, are not recorded because the sources do not label them as EN or DIN names for this grade. Product-form notes for the ASTM codes were not read from a source.'
  - The ulprospector datasheet for B-2 was not opened (HTTP 403). The PubChem GHS record for nickel was not reachable (a verification page was returned), so the hazard data rest on the Haynes SDS and the NIOSH page.
  - The Ni4Mo temperature uses the non-canonical benchmark phase_formation_temperature, and the Hardness values use hardness_rockwell_b; both names are not in property-canon.yaml.
  - The Ni4Mo temperature comes from a Haynes brochure that is written for B-3; the B-2 statement in it is quoted, and no separate B-2 datasheet with a time or temperature was found.
  - The NIOSH exposure limits apply to airborne nickel dust or fume, not to the solid alloy. They are recorded as context, not as a property of the alloy.
  - The European Commission critical raw materials list was not checked for nickel and molybdenum; only the USGS 2025 list is recorded.
  - The Haynes B-2 nominal chromium, iron, manganese and cobalt values are printed as maxima or less than values in the SDS; they are described in words in the recipe and not entered as numbers.
sources:
  rolled-b2:
    title: HASTELLOY B-2 Data Sheet, Rolled Alloys, Bulletin No. 303U (10/11)
    id: Rolled Alloys Bulletin 303U
    url: https://www.rolledalloys.ca/wp-content/uploads/HASTELLOY-B-2_Datasheet-rolled-alloys.pdf
    year: 2011
    kind: datasheet
    license: Distributor datasheet, general information, no warranty (cited, not reproduced)
  rolled-b2-page:
    title: HASTELLOY B-2 product page, Rolled Alloys
    id: Rolled Alloys product page, nickel alloys
    url: https://www.rolledalloys.ca/products/nickel/hastelloy-b-2/
    kind: web
    license: Distributor web page (cited, not reproduced)
  tachart-b2:
    title: HASTELLOY B2 alloy data page (Tachart)
    id: Tachart product page, ?p=479
    url: https://www.tachart.com/?p=479
    kind: web
    license: Supplier web page, illustrative data (cited, not reproduced)
  haynes-sds:
    title: Safety Data Sheet H2071-10, Corrosion-Resistant Alloys and High-Temperature Alloys, Haynes International (copy hosted by General Air)
    id: Haynes International SDS H2071-10
    url: https://amp.generalair.com/MsdsDocs/WWH207110S.pdf
    year: 2020
    kind: datasheet
    license: Manufacturer safety data sheet (cited, not reproduced)
  haynes-glance:
    title: 'Alloy at a Glance: HASTELLOY B-3 alloy, Haynes International, H-2101E (with B-2 comparison rows)'
    id: Haynes International H-2101E
    url: https://haynesintl.com/wp-content/uploads/2023/09/alloy-at-glance-b-3.pdf
    year: 2020
    kind: datasheet
    license: Manufacturer brochure (cited, not reproduced)
  haynes-b3-brochure:
    title: HASTELLOY B-3 alloy brochure, Haynes International (Principal Features, Thermal Stability section, comparison with B-2)
    id: Haynes International brochure, B-3 alloy
    url: https://haynesintl.com/wp-content/uploads/2024/08/pdf-alloy-b-3.pdf
    year: 2024
    kind: datasheet
    license: Manufacturer brochure (cited, not reproduced)
  usgs-mcs2026-nickel:
    title: Mineral Commodity Summaries 2026, Nickel
    id: USGS MCS 2026, February 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  usgs-mcs2026-molybdenum:
    title: Mineral Commodity Summaries 2026, Molybdenum
    id: USGS MCS 2026, February 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-molybdenum.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  usgs-crit2025:
    title: About the 2025 List of Critical Minerals (USGS)
    id: USGS final 2025 List of Critical Minerals
    url: https://www.usgs.gov/programs/mineral-resources-program/science/about-2025-list-critical-minerals
    year: 2025
    kind: web
    license: public domain (USGS)
  niosh-npg-ni:
    title: 'NIOSH Pocket Guide to Chemical Hazards: Nickel metal and other compounds (as Ni)'
    id: CDC NIOSH NPG npgd0445
    url: https://www.cdc.gov/niosh/npg/npgd0445.html
    kind: handbook
    license: public domain (CDC)
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 24
  unreachable: 3
  caveats: 5
  note: 'Read by an AI assistant on 2026-11-01 from the pages and PDFs named in each entry. Unreachable: Haynes B-2 product page (404), ulprospector datasheet (403), suppliersonline (503), PubChem nickel record (verification page). Caveats: strengths are distributor values for sheet and plate with no temper; corrosion rates are from one Haynes table; the 750 °C Ni4Mo statement comes from a B-3 brochure; the melting point is approximate; supply shares are calculated.'
story:
  recipe:
    line: Hastelloy B-2 is a nickel-molybdenum alloy. Nickel is the matrix and molybdenum is the main alloying element, and the other elements are kept low. The Haynes SDS gives the nominal composition as 69 % nickel and 28 % molybdenum, and Rolled Alloys gives the specified molybdenum range as 26 to 30 %.
    parts:
      - name: Nickel
        symbol: Ni
        share: balance; nominal 69 %
        role: Matrix metal of the alloy; it gives the austenitic structure that the molybdenum-rich composition relies on.
      - name: Molybdenum
        symbol: Mo
        share: nominal 28 %; specified 26 to 30 %
        role: Main alloying element. It gives resistance to reducing acids such as hydrochloric and sulfuric acid.
      - name: Minor elements (chromium, iron, manganese, cobalt, silicon, carbon)
        symbol: Cr, Fe, Mn, Co, Si, C
        share: each kept low; specified maxima on the Rolled Alloys composition table
        role: Limit impurities and the second phases that can form in the microstructure. Chromium is kept very low, which is why the alloy is not suited to oxidising media.
  risk_groups:
    - title: For people
      level: 1
      verdict: Solid alloy; dust and fume carry the risk
      lead: The Haynes SDS says the health hazards do not apply to the solid alloy under normal handling, but dust and fume from cutting, grinding or welding can carry hazards.
      points:
        - label: The solid
          line: Haynes says the health hazards 'do not apply under normal handling and use of these products in solid form'.
        - label: Dust and fume
          line: The Haynes SDS lists H350 (may cause cancer), H317 and H334 (sensitisation) and H315 for the product group. NIOSH gives the nickel limit as 'Ca TWA 0.015 mg/m3' and says the IDLH is 'Ca [10 mg/m3 (as Ni)]'.
        - label: Welding
          line: If the alloy is welded or melted, the Haynes Wire Company SDS for welding products (HW-7031) also applies, according to the Haynes SDS.
    - title: In service
      lead: These are the failure routes printed in the sources. Each one is a manufacturer statement or a laboratory table, not a field incident.
      points:
        - label: Oxidising conditions
          line: Rolled Alloys says the alloy 'should NOT be used in oxidizing media or in presence of oxidizing salts', and that it does not withstand wet chlorine gas or hypochlorite bleach.
        - label: Temperature
          line: Rolled Alloys says B-2 'should not be exposed to temperatures in the 1000 - 1600°F range because of severe loss of ductility'.
        - label: Ni4Mo
          line: Haynes says B-2 suffers rapid formation of Ni4Mo at around 750°C, a phase that 'affects ductility, and reduces resistance to stress corrosion cracking'.
        - label: Heat treatment and acid
          line: In Haynes's U-bend test in "Boiling 60% H2SO4", B-2 annealed with "Annealed + 1 hour at 700˚C" is printed with "Intergranular cracking, 3 hours".
    - title: Handling and storage
      points:
        - label: Dust
          line: Cutting and grinding can produce dust with the component elements. Keep dust and fume down with local exhaust, as the usual approach for metal dust, and check the Haynes SDS for the product you handle.
        - label: Keep it away from oxidisers
          line: Keep the alloy out of oxidising salts, wet chlorine and hypochlorite bleach, which Rolled Alloys says the alloy does not withstand.
  why: Hastelloy B-2 is a nickel-molybdenum alloy made for reducing acids, and it has almost no chromium. It contains a nominal 69 % nickel and 28 % molybdenum (Haynes SDS). The Haynes table gives 15 mpy in boiling 20 % hydrochloric acid and 1.0 mpy in boiling 50 % sulfuric acid. Its specified minimum tensile strength is 110 ksi for sheet and plate. It is used in chemical plants and for bolting in strongly reducing acids, and it is the predecessor of the B-3 alloy, which Haynes says has improved structural stability.
  uses:
    - where: Chemical plants
      line: Rolled Alloys lists acetic acid production, "Methyl methacrylate production with hot 98% H2SO4", and the production of herbicides and insecticides among the applications of B-2.
    - where: Bolting in strongly reducing acids
      line: Tachart lists bolting as a use and says the alloy is commonly used for its high corrosion resistance and high temperature strength in hydrochloric acid.
    - where: Equipment in hydrochloric acid
      line: Rolled Alloys says B-2 resists hydrochloric acid at all concentrations and temperatures, and withstands wet HCl gas, sulfuric, acetic and phosphoric acids.
  can_do:
    - label: Hydrochloric acid
      value: All concentrations and temperatures
      line: Rolled Alloys says B-2 resists hydrochloric acid at all concentrations and temperatures.
    - label: Reducing-acid corrosion
      benchmark: uniform_corrosion_rate
      value: 15 mpy in boiling 20 % HCl
      line: The Haynes Alloy at a Glance table gives 15 mpy in boiling 20 % hydrochloric acid and 1.0 mpy in boiling 50 % sulfuric acid.
    - label: Minimum strength
      benchmark: ultimate_tensile_strength
      value: 110 ksi minimum
      line: Rolled Alloys gives a minimum specified tensile strength of 110 ksi and a minimum specified yield strength of 51 ksi for sheet and plate.
    - label: Typical strength
      benchmark: ultimate_tensile_strength
      value: 130 ksi typical
      line: Rolled Alloys gives a typical tensile strength of 130 ksi for sheet and plate.
  compare: In the Haynes table of boiling acids, B-2 corrodes at 15 mpy in boiling 20 % hydrochloric acid, a higher rate than B-3 in the same table. In boiling 50 % sulfuric acid both alloys show low rates, with B-2 at 1.0 mpy. Haynes says B-3 has improved structural stability compared with B-2 and resists stress corrosion cracking better. Compared with oxidising conditions, B-2 has almost no chromium and is not used where oxidising salts are present.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Tensile strength
      benchmark: ultimate_tensile_strength
    - label: Yield strength
      benchmark: yield_strength
  handling:
    - Treat dust and fume as the hazard; the Haynes SDS says the health hazards do not apply to the solid under normal handling.
    - Specify the form and temper, because the Rolled Alloys strength values are for sheet and plate and do not state the temper.
    - Keep the alloy away from oxidising salts, wet chlorine and hypochlorite bleach.
    - For welding, the Haynes Wire Company SDS for welding products (HW-7031) also applies.
  good_for:
    - 'Reducing acids: 1.0 mpy in boiling 50 % sulfuric acid, per the Haynes table.'
    - Hydrochloric acid service at all concentrations and temperatures, per Rolled Alloys.
    - Acetic acid and methyl methacrylate production equipment, per the Rolled Alloys application list.
  watch_out:
    - 'No chromium: not for oxidising media, oxidising salts, wet chlorine or hypochlorite bleach.'
    - Severe loss of ductility when exposed to the "1000 - 1600°F range", per Rolled Alloys.
    - Ni4Mo forms rapidly at around 750°C, per Haynes, which affects ductility and stress corrosion cracking resistance.
    - Intergranular cracking after annealing plus 1 hour at 700 °C, reported by Haynes as 'Intergranular cracking, 3 hours'.
  verdict: Hastelloy B-2 is the nickel-molybdenum alloy for hot reducing acids, with 15 mpy in boiling 20 % hydrochloric acid in the Haynes table. It is not for oxidising service, and Rolled Alloys warns of loss of ductility in the "1000 - 1600°F range".