spore: profile
id: duplex-2101
spore_version: 0.2
family: stainless-duplex
name: Lean duplex stainless steel 2101 (UNS S32101)
abbreviation: '2101'
role: Lean duplex stainless steel for general process service, with high strength and chloride stress corrosion cracking resistance at lower nickel
category: metals
type: steels-and-stainless
summary: |
  Lean duplex stainless steel 2101 (UNS S32101, EN 1.4162, marketed by Outokumpu as LDX 2101) has 21.0 to 22.0 % chromium, 4.00 to 6.00 % manganese, 1.35 to 1.70 % nickel and 0.20 to 0.25 % nitrogen. Atlas Steels prints a typical annealed density of 7800 kg/m3, a modulus of 200 GPa and a minimum ASTM A240 tensile strength of 650 MPa with 450 MPa proof strength. Rolled Alloys prints a melting range of 2525 to 2630 °F and a usable limit of 600 °F. The data book prints a fatigue strength of 72.5 ksi at 2 million cycles for polished bars.
best_for: 'Chloride-bearing process equipment where a 300 series grade is too weak or too prone to chloride stress cracking, and nickel cost matters: the grade gives about double the 0.2 % yield of 304 and 316 and no SCC in the boiling CaCl2 U-bend test'
weakest_at: 'Use above about 300 °C: Atlas says held above 300 °C the grade embrittles and only a full solution anneal restores it, and no space-environment data (radiation, outgassing, cryogenic toughness) were found'
identity:
  formula: 'Fe-based lean duplex (ferritic-austenitic) stainless steel: Fe balance, Cr 21.0 to 22.0 %, Mn 4.00 to 6.00 %, Ni 1.35 to 1.70 %, N 0.20 to 0.25 %, Mo 0.10 to 0.80 %, Cu 0.10 to 0.80 %, C 0.040 % maximum, Si 1.00 % maximum, P 0.040 % maximum, S 0.030 % maximum'
  source: atlas2101
  where: Composition Specification table (Atlas Steels 2101 data sheet); the same limits appear in the Chemical Composition table of the Rolled Alloys data sheet
  designations:
    - system: UNS
      code: S32101
      source: atlas2101
      where: Grade Specification Comparison table, UNS No. column
    - system: EN
      code: '1.4162'
      source: atlas2101
      where: Grade Specification Comparison table, Euronorm No. column
    - system: EN name
      code: X2CrMnNiN 21-5-1
      source: industeel-dop
      where: Title line, X2CrMnNiN 21-5-1 (1.4162), EN 10088-4:2009
    - system: ASTM
      code: A240
      note: plate, sheet and strip
      source: atlas2101
      where: Specified Properties paragraph, ASTM A240/A240M
    - system: ASME
      code: SA-240
      source: rolled-ds
      where: 'Specifications line, ASME: SA-240'
    - system: Trade name
      code: LDX 2101
      source: rolled-ds
      where: Title line, LDX 2101 Duplex Stainless Steel
tags:
  environments: []
  stresses: []
  applications:
    - structures
    - propulsion-and-tanks
    - mechanisms
properties:
  - benchmark: density
    label: Density, typical, annealed
    value: 7800
    unit: kg/m3
    scope: material
    conditions:
      temper: annealed
      basis: typical values in the annealed condition
    method: Typical value printed in a supplier data sheet
    status: ground
    source: atlas2101
    where: Physical Properties table, Grade 2101, column Density (kg/m3)
  - benchmark: melting_point
    label: Melting range
    value: 2525
    value_high: 2630
    bound: range
    unit: °F
    scope: material
    conditions:
      basis: melting range as printed
    method: Melting range printed in a manufacturer data sheet
    status: ground
    source: rolled-ds
    where: Physical Properties block, Melting Range 2525-2630 °F
  - benchmark: elastic_modulus
    label: Elastic modulus, typical, annealed
    value: 200
    unit: GPa
    scope: material
    conditions:
      temper: annealed
      basis: typical values in the annealed condition
    method: Typical value printed in a supplier data sheet
    status: ground
    source: atlas2101
    where: Physical Properties table, Grade 2101, column Elastic Modules (GPa)
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 100 °C, typical, annealed
    value: 16
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: 100 °C
      temper: annealed
    method: Typical value printed in a supplier data sheet
    status: ground
    source: atlas2101
    where: Physical Properties table, Grade 2101, column Thermal Conductivity at 100°C (W/m.K)
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 300 °C, typical, annealed
    value: 18
    unit: W/(m·K)
    scope: material
    conditions:
      temperature: 300 °C
      temper: annealed
    method: Typical value printed in a supplier data sheet
    status: ground
    source: atlas2101
    where: Physical Properties table, Grade 2101, column Thermal Conductivity at 300°C (W/m.K)
  - benchmark: specific_heat
    label: Specific heat capacity, 0 to 100 °C, typical, annealed
    value: 530
    unit: J/(kg·K)
    scope: material
    conditions:
      temperature_range: 0 to 100 °C
      temper: annealed
    method: Typical value printed in a supplier data sheet
    status: ground
    source: atlas2101
    where: Physical Properties table, Grade 2101, column Specific Heat 0-100°C (J/kg.K)
  - benchmark: cte
    label: Mean coefficient of thermal expansion, 0 to 100 °C
    value: 13
    unit: µm/m/°C
    scope: material
    conditions:
      temperature_range: 0 to 100 °C
      temper: annealed
    method: Typical value printed in a supplier data sheet
    status: ground
    source: atlas2101
    where: Physical Properties table, Mean Coefficient of Thermal Expansion 0-100°C (µm/m/°C)
  - benchmark: cte
    label: Mean coefficient of thermal expansion, 0 to 300 °C
    value: 14
    unit: µm/m/°C
    scope: material
    conditions:
      temperature_range: 0 to 300 °C
      temper: annealed
    method: Typical value printed in a supplier data sheet
    status: ground
    source: atlas2101
    where: Physical Properties table, Mean Coefficient of Thermal Expansion 0-300°C (µm/m/°C)
  - benchmark: yield_strength
    label: Yield strength 0.2 % proof, minimum, ASTM A240 plate
    value: 450
    bound: lower
    unit: MPa
    scope: material
    conditions:
      spec: ASTM A240
      form: plate over 5 mm thick
      measure: 0.2 % proof stress, minimum
    method: Minimum value printed in a supplier data sheet quoting ASTM A240
    status: ground
    source: atlas2101
    where: Mechanical Property Specification table, Grade 2101, column 0.2% Proof (MPa) min
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, minimum, ASTM A240 plate
    value: 650
    bound: lower
    unit: MPa
    scope: material
    conditions:
      spec: ASTM A240
      form: plate over 5 mm thick
    method: Minimum value printed in a supplier data sheet quoting ASTM A240
    status: ground
    source: atlas2101
    where: Mechanical Property Specification table, Grade 2101, column Tensile Strength (MPa) min
  - benchmark: elongation
    label: Elongation, minimum, ASTM A240 plate
    value: 30
    bound: lower
    unit: '%'
    scope: material
    conditions:
      spec: ASTM A240
      form: plate over 5 mm thick
      gauge_length: 50 mm
    method: Minimum value printed in a supplier data sheet quoting ASTM A240
    status: ground
    source: atlas2101
    where: Mechanical Property Specification table, Grade 2101, column Elongation (% in 50mm) min
  - benchmark: hardness
    label: Hardness, maximum, Brinell, ASTM A240
    value: 290
    bound: upper
    unit: HB
    scope: material
    conditions:
      spec: ASTM A240
      scale: Brinell
    method: Maximum value printed in a supplier data sheet quoting ASTM A240
    status: ground
    source: atlas2101
    where: Mechanical Property Specification table, Grade 2101, column Brinell (HB) max
  - benchmark: max_service_temp
    label: Useful upper temperature limit
    value: 600
    unit: °F
    scope: material
    conditions:
      basis: stated as useful up to 600 °F, no duration given
      environment: not stated
    method: Value printed in a manufacturer data sheet
    status: ground
    source: rolled-ds
    where: Features list, Useful up to 600°F
  - benchmark: min_service_temp
    label: Lower temperature limit for use
    value: -50
    unit: °C
    scope: material
    conditions:
      basis: not generally recommended below -50 °C because of the ductile-to-brittle transition
    method: Value printed in a supplier data sheet
    status: ground
    source: atlas2101
    where: Low Temperature Performance section
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, minimum, elevated temperature, 212 °F, plate
    value: 85.6
    bound: lower
    unit: ksi
    scope: material
    conditions:
      temperature: 212 °F
      form: plate
      basis: minimum elevated temperature tensile properties
    method: Minimum value printed in a manufacturer data sheet
    status: ground
    source: rolled-ds
    where: Minimum Elevated Temperature Tensile Properties, Plate, column 212, row Ultimate Tensile Strength
  - benchmark: yield_strength
    label: Yield strength 0.2 % proof, minimum, elevated temperature, 212 °F, plate
    value: 55.1
    bound: lower
    unit: ksi
    scope: material
    conditions:
      temperature: 212 °F
      form: plate
      basis: minimum elevated temperature tensile properties
    method: Minimum value printed in a manufacturer data sheet
    status: ground
    source: rolled-ds
    where: Minimum Elevated Temperature Tensile Properties, Plate, column 212, row 0.2% Yield Strength
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, minimum, elevated temperature, 572 °F, plate
    value: 78.3
    bound: lower
    unit: ksi
    scope: material
    conditions:
      temperature: 572 °F
      form: plate
      basis: minimum elevated temperature tensile properties
    method: Minimum value printed in a manufacturer data sheet
    status: ground
    source: rolled-ds
    where: Minimum Elevated Temperature Tensile Properties, Plate, column 572, row Ultimate Tensile Strength
  - benchmark: yield_strength
    label: Yield strength 0.2 % proof, minimum, elevated temperature, 572 °F, plate
    value: 43.5
    bound: lower
    unit: ksi
    scope: material
    conditions:
      temperature: 572 °F
      form: plate
      basis: minimum elevated temperature tensile properties
    method: Minimum value printed in a manufacturer data sheet
    status: ground
    source: rolled-ds
    where: Minimum Elevated Temperature Tensile Properties, Plate, column 572, row 0.2% Yield Strength
  - benchmark: fatigue_strength
    label: Fatigue strength, pulsating tension, 2 million cycles, 50 % probability of rupture
    value: 72.5
    unit: ksi
    scope: material
    conditions:
      cycles: 2000000
      load_ratio: 0.1
      environment: air, room temperature
      specimen: round polished bars from hot rolled plate
      basis: 50 % probability of rupture; correction factors needed for surface, notches and welds
    method: Test value printed in a manufacturer data book
    status: ground
    source: rolled-db
    where: Pulsating tensile fatigue table, column Fatigue Strength ksi, LDX 2101 column
corrosion:
  - environment: Chloride stress corrosion cracking, boiling 40 % CaCl2 at 212 °F, 500 hours, U-bend
    headline: LDX 2101 showed no cracking in the U-bend test, where 304/304L cracked in under 150 hours.
    effect: Rolled Alloys prints No SCC for LDX 2101 and SCC cracking (<150 hours) for 304/304L in the same test. It calls the duplex structure the reason for the grade excellent SCC resistance.
    rating: unknown
    conditions:
      basis: U-bend test, 500 hours, boiling 40 % CaCl2 solution at 212 °F
    source: rolled-ds
    where: Corrosion section, Stress Corrosion Cracking, U-Bend Testing table
  - environment: Chloride pitting and crevice attack
    headline: Atlas gives a PRE of 26, slightly above 316, and in practice pitting and crevice behaviour lies between 304 and 316.
    effect: Atlas says the Pitting Resistance Equivalent of 2101 is 26, slightly higher than that of 316, and that actual pitting and crevice behaviour is generally between 304 and 316. Rolled Alloys says pitting resistance is comparable to 316L.
    rating: moderate
    conditions:
      basis: PRE from the Atlas data sheet; no critical pitting temperature number was read (the Rolled Alloys CPT chart is an image)
    source: atlas2101
    where: Corrosion Resistance section, first and second paragraphs
  - environment: Caustic white liquor, 21 days, 194 °F and 217 °F
    headline: LDX 2101 showed a corrosion rate of 0.000 mpy in liquor phase testing, where 316/316L showed 0.002 mpy.
    effect: In the liquor phase test at 194 °F for 21 days, LDX 2101 lost 0.6 and 0.4 mg and showed 0.000 mpy; 304/304L showed 0.001 and 0.000 mpy and 316/316L showed 0.002 and 0.002 mpy. At 217 °F, 316/316L showed 0.002 mpy and LDX 2101 showed 0.000 mpy.
    rating: unknown
    conditions:
      basis: liquor phase test of a caustic white liquor composition, 21 days
    source: rolled-db
    where: Caustic (White Liquor Testing) section, Liquor Phase Testing tables at 194 °F and 217 °F, column Corrosion Rate mpy
  - environment: Hydrochloric, sulphuric, nitric, formic and phosphoric acids, critical temperature for 0.005 ipy corrosion
    headline: LDX 2101 has a higher critical temperature than 316/316L in 1 % HCl, 10 % H2SO4 and 50 % formic acid, but a lower one in 96.4 % H2SO4.
    effect: Rolled Alloys Table 13 prints 55 °C for LDX 2101 in 1 % HCl (316/316L 30 °C), 75 °C in 10 % H2SO4 (50 °C), and 30 °C in 96.4 % H2SO4 (45 °C). In 50 % formic acid the figures are 95 °C (40 °C). In 65 % HNO3 they are 105 °C (100 °C), and in 83 % H3PO4 they are 40 °C (65 °C).
    rating: moderate
    conditions:
      basis: critical temperature for 0.005 ipy corrosion as printed in the Rolled Alloys tables
    source: rolled-db
    where: Sulfuric and Hydrochloric Acids table (Table 13), Nitric Acid, Organic Acids and Phosphoric Acid tables
  - environment: Intergranular corrosion, ASTM A262 practices B and E
    headline: LDX 2101 passes the ASTM A262 practice B and E tests, which is typical of duplex grades.
    effect: Rolled Alloys says LDX 2101 passes ASTM A 262 method B (Streicher) and method E (Strauss). Atlas says the grade has good resistance to intergranular corrosion.
    rating: unknown
    conditions:
      basis: ASTM A262 practices B and E as printed
    source: rolled-db
    where: Intergranular Corrosion paragraph under Corrosion Resistance
risks:
  hazards:
    - text: 'Uddeholm safety information sheet for steel articles, Nickel entry: H317 May cause an allergic skin reaction. H351 Suspected of causing cancer by inhalation. H372 Causes damage to organs through prolonged or repeated exposure by inhalation. Signal word DANGER. The sheet is for Uddeholm alloys, not for 2101.'
      ghs:
        - H317
        - H351
        - H372
      source: uddeholm-sis
      where: Classification of the major hazard substances, Nickel entry, Hazard Statements
    - text: 'The sheet states the CLP rule for steels: more than 10 % nickel is STOT RE1, 1 to 10 % nickel is STOT RE2, and more than 1 % nickel is Carcinogen Category 2. Applied as printed to the 1.35 to 1.70 % nickel range of 2101, the rule gives STOT RE2 and Carcinogen Category 2. This is an application of the rule, not a classification read from a 2101 sheet.'
      ghs: []
      source: uddeholm-sis
      where: Note under the Nickel entry, CLP rule for steels
    - text: 'Chromium entry: H317 May cause an allergic skin reaction. H350i May cause cancer by inhalation. Welding and flame cutting fumes may contain hexavalent chromium compounds.'
      ghs:
        - H317
        - H350i
      source: uddeholm-sis
      where: Classification of the major hazard substances, Chromium entry, and the welding fume paragraph
    - text: The sheet says alloys containing nickel or chromium may cause health hazards by inhalation of dusts and fumes produced by grinding, polishing, welding or cutting, and that prolonged or repeated skin contact may cause dermatitis in nickel-sensitised persons.
      ghs: []
      source: uddeholm-sis
      where: Description of Hazards
  failure_risks:
    - mode: Embrittlement from exposure above 300 °C
      trigger: Held at temperatures above 300 °C, which Atlas says duplex grades are almost never used above
      consequence: The grade embrittles, and only a full solution anneal rectifies it (Atlas).
      severity: moderate
      source: atlas2101
      where: Heat Resistance section
    - mode: Ductile-to-brittle transition at low temperature
      trigger: Service below -50 °C
      consequence: Atlas says duplex stainless steels, including 2101, are not generally recommended below -50 °C because of the ductile-to-brittle transition.
      severity: moderate
      source: atlas2101
      where: Low Temperature Performance section
    - mode: Fatigue cracking at notches, surfaces and welds
      trigger: Cyclic loading; the 72.5 ksi fatigue strength is for round polished bars
      consequence: Rolled Alloys says correction factors for surface roughness, notches and welds are required, and the fatigue strength corresponds approximately to the yield strength of the duplex steel.
      severity: moderate
      source: rolled-db
      where: Fatigue table and the paragraph above it
  side_effects: []
  handling:
    - text: Solution anneal at 1020 to 1080 °C, then cool rapidly. The grade cannot be hardened by thermal treatment, but it work hardens (Atlas).
      source: atlas2101
      where: Heat Treatment section, Solution Treatment (Annealing)
    - text: Rolled Alloys gives the solution annealing range as 1870-1975 °F, with rapid cooling recommended to limit secondary phases.
      source: rolled-db
      where: Heat Treatment section
    - text: Weld with 2209 filler so the deposit keeps a balanced duplex structure. Keep heat input low, and use no pre- or post-heat. Atlas says welding without filler may be possible.
      source: atlas2101
      where: Welding section
    - text: Bending and forming need larger equipment than for austenitic grades, and severe cold work such as cold heading needs an intermediate anneal (Atlas).
      source: atlas2101
      where: Fabrication section
  mitigations: []
uses:
  - application: structures
    device: Chemical process pressure vessels, piping and heat exchangers
    example: Rolled Alloys lists chemical process pressure vessels, piping and heat exchangers, pulp and paper mill equipment, mixers and agitators, storage tanks, waste water handling systems and ethanol production as its applications for LDX 2101.
    source: rolled-ds
    where: Applications list of the Rolled Alloys data sheet
  - application: structures
    device: External stiffeners on an FGD absorber tower
    example: Rolled Alloys says LDX 2101 was used for external stiffeners on a 2205 duplex FGD absorber tower in the western United States instead of 304L, because it allowed a lighter section, needed no painting and matched the strength and expansion of 2205.
    source: rolled-db
    where: Power Plants Applications paragraph
  - application: mechanisms
    device: Screw conveyor shaft in a mechanical pulping mill
    example: The 316 stainless shaft had suffered fatigue failure after 12 months, and LDX 2101 was selected to replace it on the basis of its improved mechanical properties.
    source: rolled-db
    where: Pulp and Paper Applications paragraph
supply:
  - subject: Nickel (world mine production, nickel content, 2025 estimate)
    producers:
      - country: Indonesia
        share_percent: 66.7
        year: 2025
      - country: Philippines
        share_percent: 6.9
        year: 2025
      - country: Russia
        share_percent: 5.1
        year: 2025
      - country: New Caledonia
        share_percent: 3.6
        year: 2025
      - country: Canada
        share_percent: 3.6
        year: 2025
    critical_lists: []
    recycling: 'USGS: nickel recovered from scrap accounted for approximately 60 % of apparent consumption in 2025; most recycled nickel was used to produce new alloys and stainless steel.'
    substitutes:
      - 'USGS: low-nickel, duplex or ultrahigh-chromium stainless steels have been substituted for austenitic grades in construction, which is the substitution route 2101 itself represents.'
    source: usgs-ni-2026
    where: World Mine Production and Reserves table, 2025e world total 3,900,000 t; shares calculated for this profile from Indonesia 2,600,000, Philippines 270,000, Russia 200,000, New Caledonia 140,000 and Canada 140,000. Recycling and Substitutes paragraphs.
  - subject: Chromium (world mine production, chromium content, 2025 estimate)
    producers:
      - country: South Africa
        share_percent: 45.1
        year: 2025
      - country: Turkey
        share_percent: 17.6
        year: 2025
      - country: Kazakhstan
        share_percent: 13.7
        year: 2025
      - country: India
        share_percent: 5.9
        year: 2025
    critical_lists: []
    recycling: 'USGS: recycled chromium in stainless-steel scrap receipts accounted for 21 % of U.S. apparent consumption in 2025.'
    substitutes:
      - 'USGS: chromium has no substitute in stainless steel, the leading end use.'
    source: usgs-cr-2026
    where: World Mine Production and Reserves table, 2025e world total 51,000 thousand t; shares calculated for this profile from South Africa 23,000, Turkey 9,000, Kazakhstan 7,000 and India 3,000 thousand t. Recycling and Substitutes paragraphs.
  - subject: Manganese (world mine production, manganese content, 2025 estimate)
    producers:
      - country: South Africa
        share_percent: 38
        year: 2025
      - country: Gabon
        share_percent: 25
        year: 2025
      - country: Ghana
        share_percent: 10
        year: 2025
      - country: Australia
        share_percent: 8
        year: 2025
      - country: Brazil
        share_percent: 4
        year: 2025
    critical_lists: []
    recycling: 'USGS: scrap recovery specifically for manganese was negligible; manganese is recovered along with iron from steel slag.'
    substitutes:
      - 'USGS: manganese has no satisfactory substitute in its major applications.'
    source: usgs-mn-2026
    where: World Mine Production and Reserves table, 2025e world total 20,000 t (rounded); shares calculated for this profile from South Africa 7,600, Gabon 5,000, Ghana 2,000, Australia 1,600 and Brazil 800. Recycling and Substitutes paragraphs.
documents:
  - title: LDX 2101 Duplex Stainless Steel Data Sheet, Rolled Alloys (Bulletin No. 2100, rev 12/16)
    type: datasheet
    url: https://www.rolledalloys.com/wp-content/uploads/2022/07/LDX-2101_Data-sheet-rolled-alloys.pdf
    year: 2016
  - title: LDX 2101 Data Book, Rolled Alloys (Bulletin No. 1101, rev 12/16)
    type: datasheet
    url: https://www.rolledalloys.ca/wp-content/uploads/2022/07/LDX-2101_Data-book-rolled-alloys.pdf
    year: 2016
  - title: Stainless Steel 2101 Grade Data Sheet, Atlas Steels (rev 27/04/2021)
    type: datasheet
    url: https://atlassteels.com.au/wp-content/uploads/2021/06/Stainless-Steel-2101-Grade-Data-Sheet-27-04-21.pdf
    year: 2021
  - title: Declaration of performance DOP-IB053, X2CrMnNiN 21-5-1 (1.4162), ArcelorMittal Industeel
    type: datasheet
    url: https://industeel.arcelormittal.com/fichier/dop-ib-1-4162-x2crmnnin-21-5-1-ce
  - 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: Chromium'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
    year: 2026
  - title: 'USGS Mineral Commodity Summaries 2026: Manganese'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-manganese.pdf
    year: 2026
  - title: Alloys delivered from Uddeholms AB, material safety information sheet (release 2010-01-04, review 2018-09-10)
    type: sds
    url: https://www.uddeholm.com/app/uploads/sites/235/2024/05/Alloys-delivered-from-Uddeholms-AB.pdf
gaps:
  - 'Electrical resistivity: Atlas prints 800 nΩ·m at 20 °C, but the importer unit table has no nΩ·m entry, so the row is left out. Add it once the unit is supported.'
  - 'Density conflict: the Rolled Alloys data sheet prints 0.278 lb/in3 and its data book prints 0.281 lb/in3. The file uses the Atlas typical value of 7800 kg/m3 only.'
  - 'Service temperature conflict: Rolled Alloys prints a usable limit of 600 °F (about 316 °C), and Atlas says embrittlement starts above 300 °C and duplex grades are almost never used above 300 °C. Both are kept as printed; the file does not resolve them.'
  - 'Critical pitting temperature: the Rolled Alloys data book gives a CPT chart (ASTM G 150, 5.8 % NaCl) that is an image in the PDF, so no CPT number was read. The PRE of 26 is from Atlas.'
  - 'The Rolled Alloys ASME allowable stress table (ksi by temperature, 200 to 600 °F) is not entered: it is not a canonical property and the allowable stress basis is not stated in a way the file can cite cleanly.'
  - 'Cold-rolled plate and sheet tensile values (94 ksi and 101 ksi, and 65 ksi and 77 ksi yield, by thickness) are left out: the file uses the ASTM A240 minimums instead, which match the Atlas specification.'
  - No process route (melting and refining) was read from a primary source, so the recipe has no process description beyond the solution annealing treatment.
  - Atomic weights were not read from a fetched page and are left out of the recipe parts.
  - No radiation, outgassing, atomic-oxygen, cold-welding or cryogenic toughness data were found for 2101 in this run. Atlas says the grade is not generally recommended below -50 °C.
  - Critical-mineral list status for nickel, chromium and manganese was not read from the official list in this run, so critical_lists is left empty for all three subjects.
  - No media file was fetched or licensed for this profile, so the media key is absent.
  - The Industeel EN 10088-4 minimum values are in a garbled table in the extracted text and were not used. The ASTM A240 values from Atlas and Rolled Alloys were used instead.
  - No JIS, AISI or Swedish SS designation was printed by the sources read for this grade; the Atlas comparison table prints a dash in those columns.
  - Hazard classes come from the Uddeholm sheet for steel articles and its CLP rule, not from a 2101 sheet or PubChem. No SDS for the 2101 base alloy was opened.
  - Hardness is not a canonical property name in spores/property-canon.yaml, so the benchmark is written as hardness with the HB unit as printed.
  - Fatigue strength is in ksi as printed; the canonical unit in property-canon is MPa and the importer converts it.
sources:
  atlas2101:
    title: Stainless Steel 2101 Grade Data Sheet, Atlas Steels (rev 27/04/2021)
    id: UNS S32101, EN 1.4162; ASTM A240/A240M
    url: https://atlassteels.com.au/wp-content/uploads/2021/06/Stainless-Steel-2101-Grade-Data-Sheet-27-04-21.pdf
    year: 2021
    kind: datasheet
    license: Distributor data sheet, reference only (cited, not reproduced)
  rolled-ds:
    title: LDX 2101 Duplex Stainless Steel Data Sheet, Rolled Alloys (Bulletin No. 2100)
    id: UNS S32101, W. Nr./EN 1.4162, ASTM A 240, ASME SA-240
    url: https://www.rolledalloys.com/wp-content/uploads/2022/07/LDX-2101_Data-sheet-rolled-alloys.pdf
    year: 2016
    kind: datasheet
    license: Manufacturer data sheet (cited, not reproduced)
  rolled-db:
    title: LDX 2101 Data Book, Rolled Alloys (Bulletin No. 1101)
    id: UNS S32101, W. Nr./EN 1.4162
    url: https://www.rolledalloys.ca/wp-content/uploads/2022/07/LDX-2101_Data-book-rolled-alloys.pdf
    year: 2016
    kind: datasheet
    license: Manufacturer data book (cited, not reproduced)
  industeel-dop:
    title: Declaration of performance DOP-IB053, X2CrMnNiN 21-5-1 (1.4162), ArcelorMittal Industeel
    id: X2CrMnNiN 21-5-1 (1.4162), EN 10088-4:2009
    url: https://industeel.arcelormittal.com/fichier/dop-ib-1-4162-x2crmnnin-21-5-1-ce
    kind: datasheet
    license: Manufacturer declaration (cited, not reproduced)
  usgs-ni-2026:
    title: Mineral Commodity Summaries 2026, Nickel
    id: USGS MCS 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  usgs-cr-2026:
    title: Mineral Commodity Summaries 2026, Chromium
    id: USGS MCS 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  usgs-mn-2026:
    title: Mineral Commodity Summaries 2026, Manganese
    id: USGS MCS 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-manganese.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  uddeholm-sis:
    title: Alloys delivered from Uddeholms AB, material safety information sheet (release 2010-01-04, review 2018-09-10)
    url: https://www.uddeholm.com/app/uploads/sites/235/2024/05/Alloys-delivered-from-Uddeholms-AB.pdf
    kind: datasheet
    license: Manufacturer safety information sheet (cited, not reproduced)
license: CC-BY-4.0
updated: '2026-10-26'
review:
  status: draft
  method: assistant
  checked_values: 19
  unreachable: 0
  caveats: 6
  note: 'Values were read by an AI assistant on 2026-10-26 from the PDFs named in each entry. Caveats: the density differs between the Atlas and Rolled Alloys documents; the Rolled Alloys usable limit (600 °F) and the Atlas embrittlement threshold (300 °C) differ; the melting range and room-temperature tensile figures are Imperial as printed; the hazard classes come from a steel-article sheet for Uddeholm alloys; the CPT chart is an image and was not read; the EN name is printed with a space in the source.'
story:
  risk_groups:
    - title: For people
      lead: Dust and fumes from working the steel carry the hazards, because the sources classify nickel and chromium, not the massive metal.
      level: 1
      verdict: Nickel and chromium classes apply to dust and fumes
      points:
        - label: Nickel in the alloy
          line: Uddeholm's safety information sheet for steel articles classes nickel with H317, H351 and H372 (DANGER). It says massive steel needs no label, but dust and fumes from grinding, polishing, welding or cutting carry the risk.
        - label: Nickel limit rule
          line: The same sheet puts steels with 1 to 10 % nickel in STOT RE2 and steels above 1 % nickel in Carcinogen Category 2. The 2101 range of 1.35 to 1.70 % nickel falls in that band, so the rule as printed points to both classes.
    - title: If it fails
      lead: These are failure routes printed in the sources. None is a measured space result.
      points:
        - label: Embrittlement above 300 °C
          line: Atlas says duplex grades embrittle when held above 300 °C and only a full solution anneal rectifies the damage.
        - label: Low-temperature brittleness
          line: Atlas says the grade is not generally recommended below -50 °C because of the ductile-to-brittle transition.
        - label: Fatigue
          line: Rolled Alloys gives 72.5 ksi fatigue strength at 2 million cycles for polished bars and says notches, welds and surface finish need correction factors. A 316 shaft in a pulp mill failed by fatigue after 12 months and was replaced with 2101.
    - title: Handling and storage
      points:
        - label: Heat treatment
          line: Atlas gives a solution anneal at 1020 to 1080 °C with rapid cooling. The grade cannot be hardened by heat treatment, only by work hardening.
        - label: Welding
          line: Atlas says weld with 2209 filler, keep heat input low, and use no pre- or post-heat.
  why: Lean duplex stainless steel 2101 gives about double the yield strength of 304 and 316 and resists chloride stress corrosion cracking, with 1.35 to 1.70 % nickel and manganese in place of most of the nickel. Atlas prints a typical annealed density of 7800 kg/m3 and a modulus of 200 GPa, and gives a minimum ASTM A240 tensile strength of 650 MPa with 450 MPa proof strength.
  uses:
    - where: Process plant and pressure equipment
      line: Rolled Alloys lists chemical process pressure vessels, piping, heat exchangers, storage tanks and mixers, with pulp and paper, waste water and ethanol uses.
    - where: Power plant and pulp mill parts
      line: Rolled Alloys describes 2101 external stiffeners on a 2205 FGD absorber tower, and a pulp mill screw conveyor shaft that replaced a fatigued 316 shaft.
  can_do:
    - label: Carry load at a lower cost
      value: 650 MPa
      benchmark: ultimate_tensile_strength
      line: The ASTM A240 minimum tensile strength is 650 MPa and the proof strength is 450 MPa (Atlas). Rolled Alloys says a lighter gauge can hold the strength of a 300 series part.
    - label: Resist chloride cracking
      value: No SCC
      line: Rolled Alloys reports no cracking in the boiling 40 % CaCl2 U-bend test at 212 °F for 500 hours, where 304/304L cracked in under 150 hours.
    - label: Stiffness
      value: 200 GPa
      benchmark: elastic_modulus
      line: The typical annealed modulus is 200 GPa (Atlas).
    - label: Use limit
      value: 600 °F
      benchmark: max_service_temp
      line: Rolled Alloys says the grade is useful up to 600 °F, while Atlas puts the embrittlement limit at 300 °C. The two are kept separate in the file.
  compare: Lean duplex 2101 sits between the 300 series austenitic grades and the 2205 duplex. Rolled Alloys says it is priced competitively with 304/304L and 316/316L, and has about double their yield strength; Atlas says its pitting resistance is between 304 and 316, and that 2205 is for higher-chloride service. The sibling 2205 profile is in this site as stainless-2205, and the austenitic siblings are stainless-304l and stainless-316.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Melting range
      benchmark: melting_point
    - label: Thermal conductivity
      benchmark: thermal_conductivity
  recipe:
    line: Lean duplex stainless steel 2101 is an iron-based ferritic-austenitic alloy. Manganese (4.00 to 6.00 %) and nitrogen (0.20 to 0.25 %) replace much of the nickel and molybdenum of 300 series grades to keep the duplex balance (Atlas, Rolled Alloys). The melting route was not read from a primary source.
    parts:
      - name: Iron
        symbol: Fe
        share: balance, printed as balance in the Rolled Alloys composition table
        role: The matrix of the alloy; the other elements are dissolved in it.
      - name: Chromium
        symbol: Cr
        share: 21.0 to 22.0 wt %
        role: Gives the corrosion and oxidation resistance; the PRE of 26 is built on it (Atlas).
      - name: Manganese
        symbol: Mn
        share: 4.00 to 6.00 wt %
        role: Keeps the ferrite-austenite balance and allows the nickel content to be reduced (Rolled Alloys).
      - name: Nickel
        symbol: Ni
        share: 1.35 to 1.70 wt %
        role: Stabilises the austenite at a much lower level than in 304 or 316 (Atlas, Rolled Alloys).
      - name: Nitrogen
        symbol: 'N'
        share: 0.20 to 0.25 wt %
        role: Adds strength and pitting resistance, and largely takes over the role of molybdenum (Atlas, Rolled Alloys).
      - name: Molybdenum
        symbol: Mo
        share: 0.10 to 0.80 wt %
        role: A small addition for corrosion resistance (Atlas).
      - name: Copper
        symbol: Cu
        share: 0.10 to 0.80 wt %
        role: Printed in the composition limits; the sources give no function.
      - name: Silicon
        symbol: Si
        share: 1.00 wt % maximum
        role: Printed in the composition limits; the sources give no function.
      - name: Carbon
        symbol: C
        share: 0.040 wt % maximum
        role: An impurity limit in the ASTM A240 composition.
      - name: Phosphorus
        symbol: P
        share: 0.040 wt % maximum
        role: An impurity limit in the ASTM A240 composition.
      - name: Sulphur
        symbol: S
        share: 0.030 wt % maximum
        role: An impurity limit in the ASTM A240 composition.
  handling:
    - Specify the form and thickness, because the ASTM A240 minimums apply to plate over 5 mm thick (Atlas).
    - Weld with 2209 filler and low heat input, with no pre- or post-heat (Atlas).
    - Control dust and fumes when grinding, polishing, welding or cutting, because the Uddeholm sheet names nickel and chromium dust and fumes as the hazard.
  good_for:
    - Chloride-bearing process equipment where 304 or 316 would be too weak or prone to chloride cracking (Rolled Alloys).
    - Welded structures and pressure parts that need high strength, where a lighter gauge saves weight (Rolled Alloys, Atlas).
    - Pulp, paper, waste water and ethanol plant, where the sources report service history (Rolled Alloys).
  watch_out:
    - Embrittlement above 300 °C, and no service above that without a solution anneal (Atlas).
    - Limited low-temperature toughness below -50 °C (Atlas).
    - Forming and bending need more equipment than austenitic grades (Atlas).
    - No vacuum, radiation or atomic-oxygen data were found for this profile.
  verdict: Lean duplex 2101 is a strong, nickel-economical stainless steel for chloride process service with a printed minimum tensile strength of 650 MPa and no SCC in the boiling CaCl2 test. Its use is limited above about 300 °C and below -50 °C, and this profile lacks space-environment numbers.