Martensitic stainless steel (EN 1.4418, X4CrNiMo16-5-1) 1.4418 (X4CrNiMo16-5-1)

spore: profile
id: stainless-14418
spore_version: 0.2
family: stainless-martensitic
name: Martensitic stainless steel (EN 1.4418, X4CrNiMo16-5-1)
abbreviation: 1.4418 (X4CrNiMo16-5-1)
role: quenched and tempered corrosion-resistant steel for shafts, axles and pump parts
category: metals
type: steels-and-stainless
summary: |
  EN 1.4418 (X4CrNiMo16-5-1) is a soft martensitic stainless steel with 15.00 to 17.00 percent chromium, 4.00 to 6.00 percent nickel and 0.80 to 1.50 percent molybdenum, according to the Deutsche Edelstahlwerke datasheets. Deutsche Edelstahlwerke sells it as Acidur 4418 and gives quenched and tempered strength levels QT760 and QT900, with minimum tensile strengths of 760 and 900 MPa. Its datasheets list shafts, axles, pump and centrifuge parts, the chemical industry and aviation and aerospace as uses.
best_for: Quenched and tempered shafts, axles and pump parts that need strength, toughness and good general corrosion resistance, with limited marine exposure (DEW)
weakest_at: 'Chloride pitting: DEW gives a risk of pitting corrosion in saturated sodium chloride and in sea water at 20 C, and welds need heat treatment afterwards (DEW)'
identity:
  formula: Fe balance; C max. 0.06; Si max. 0.7; Mn max. 1.5; P max. 0.04; S max. 0.03; Cr 15.00 to 17.00; Ni 4.00 to 6.00; Mo 0.80 to 1.50; N min. 0.02 (mass percent, DIN EN 10088-3)
  source: dew-1-4418-uk
  where: 'Title block of the English sheet: C max. 0.06, Cr 15.00 - 17.00, Ni 4.00 - 6.00, Mo 0.80 - 1.50, N >= 0.02. Si, Mn, P and S maxima from the chemical composition table (min./max. row) of the German sheet'
  designations:
    - system: EN
      code: '1.4418'
      note: Material number. Both DEW sheets print it for this grade; the composition and mechanical tables cite DIN EN 10088-3.
      source: dew-1-4418-de
      where: Normen und Bezeichnungen table, DIN EN 10088-3 row
    - system: EN name
      code: X4CrNiMo16-5-1
      note: EN name. The German sheet prints it against DIN EN 10272, the pressure vessel standard it cites for delivery.
      source: dew-1-4418-uk
      where: Title block and General comments table, EN 10088-3 row
    - system: DIN
      code: '17440'
      note: Standard number printed beside 1.4418 in the English sheet's General comments table.
      source: dew-1-4418-uk
      where: General comments table, DIN 17440 row
    - system: AFNOR
      code: Z6CND16-05-01
      source: dew-1-4418-de
      where: Normen und Bezeichnungen table, AFNOR row
    - system: SS
      code: '2387'
      note: Swedish standard number. The English sheet prints it as SIS 2387.
      source: dew-1-4418-de
      where: Normen und Bezeichnungen table, SS row
    - system: SIS
      code: '2387'
      note: Swedish standard number as printed on the English sheet (the German sheet prints SS 2387).
      source: dew-1-4418-uk
      where: General comments table, SIS row
    - system: Trade name
      code: Acidur 4418
      note: DEW trade name for this grade, printed in the header of each German sheet page.
      source: dew-1-4418-de
      where: Page header, Werkstoffdatenblatt title block
tags:
  environments: []
  stresses:
    - extreme-cold
  applications:
    - structures
    - mechanisms
properties:
  - benchmark: yield_strength
    label: Yield strength, +QT760, diameter up to 160 mm (minimum)
    value: 550
    bound: lower
    unit: MPa
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      tempering: 590 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter up to 160 mm
      basis: minimum Rp0,2
      standard: DIN EN 10088-3
    method: Room-temperature table, +QT760 row, diameter up to 160 mm, Rp0,2 as printed (minimum 550)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT760 row, diameter up to 160 mm (Rp0,2 ≥ 550)
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, +QT760, diameter up to 160 mm (range)
    value: 760
    value_high: 960
    bound: range
    unit: MPa
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      tempering: 590 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter up to 160 mm
      basis: range as printed
      standard: DIN EN 10088-3
    method: Room-temperature table, +QT760 row, Rm as printed (760 to 960)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT760 row, diameter up to 160 mm (Rm 760 - 960)
  - benchmark: elongation
    label: Elongation A5, +QT760, diameter up to 160 mm, longitudinal (minimum)
    value: 16
    bound: lower
    unit: '%'
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      tempering: 590 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter up to 160 mm
      direction: longitudinal
      gauge: A5 as printed
      basis: minimum
      standard: DIN EN 10088-3
    method: A5 longitudinal column, +QT760 row, diameter up to 160 mm, printed as a plain number (minimum 16)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT760 row, diameter up to 160 mm (A5 in %, längs ≥ 16)
  - benchmark: charpy_impact_energy
    label: Impact energy AV, +QT760, diameter up to 160 mm, longitudinal (minimum)
    value: 90
    bound: lower
    unit: J
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      tempering: 590 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter up to 160 mm
      direction: longitudinal
      test_temperature: not printed in this table
      basis: minimum
      standard: DIN EN 10088-3
    method: AV longitudinal column, +QT760 row, diameter up to 160 mm, printed as a plain number (minimum 90)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT760 row, diameter up to 160 mm (AV in J, längs ≥ 90)
  - benchmark: yield_strength
    label: Yield strength, +QT900, diameter up to 160 mm (minimum)
    value: 700
    bound: lower
    unit: MPa
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      tempering: 550 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter up to 160 mm
      basis: minimum Rp0,2
      standard: DIN EN 10088-3
    method: Room-temperature table, +QT900 row, diameter up to 160 mm, Rp0,2 as printed (minimum 700)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT900 row, diameter up to 160 mm (Rp0,2 ≥ 700)
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, +QT900, diameter up to 160 mm (range)
    value: 900
    value_high: 1100
    bound: range
    unit: MPa
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      tempering: 550 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter up to 160 mm
      basis: range as printed
      standard: DIN EN 10088-3
    method: Room-temperature table, +QT900 row, Rm as printed (900 to 1100)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT900 row, diameter up to 160 mm (Rm 900 - 1100)
  - benchmark: elongation
    label: Elongation A5, +QT900, diameter up to 160 mm, longitudinal (minimum)
    value: 16
    bound: lower
    unit: '%'
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      tempering: 550 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter up to 160 mm
      direction: longitudinal
      gauge: A5 as printed
      basis: minimum
      standard: DIN EN 10088-3
    method: A5 longitudinal column, +QT900 row, diameter up to 160 mm, printed as a plain number (minimum 16)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT900 row, diameter up to 160 mm (A5 in %, längs ≥ 16)
  - benchmark: charpy_impact_energy
    label: Impact energy AV, +QT900, diameter up to 160 mm, longitudinal (minimum)
    value: 80
    bound: lower
    unit: J
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      tempering: 550 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter up to 160 mm
      direction: longitudinal
      test_temperature: not printed in this table
      basis: minimum
      standard: DIN EN 10088-3
    method: AV longitudinal column, +QT900 row, diameter up to 160 mm, printed as a plain number (minimum 80)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT900 row, diameter up to 160 mm (AV in J, längs ≥ 80)
  - benchmark: elongation
    label: Elongation A5, +QT760, diameter 160 to 250 mm, transverse (minimum)
    value: 14
    bound: lower
    unit: '%'
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      tempering: 590 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter 160 to 250 mm
      direction: transverse
      gauge: A5 as printed
      basis: minimum
      standard: DIN EN 10088-3
    method: A5 transverse column, +QT760 row, diameter 160 to 250 mm, printed as a plain number (minimum 14)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT760 row, 160 < d ≤ 250 (A5 in %, quer ≥ 14)
  - benchmark: charpy_impact_energy
    label: Impact energy AV, +QT760, diameter 160 to 250 mm, transverse (minimum)
    value: 70
    bound: lower
    unit: J
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      tempering: 590 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter 160 to 250 mm
      direction: transverse
      test_temperature: not printed in this table
      basis: minimum
      standard: DIN EN 10088-3
    method: AV transverse column, +QT760 row, diameter 160 to 250 mm, printed as a plain number (minimum 70)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT760 row, 160 < d ≤ 250 (AV in J, quer ≥ 70)
  - benchmark: elongation
    label: Elongation A5, +QT900, diameter 160 to 250 mm, transverse (minimum)
    value: 14
    bound: lower
    unit: '%'
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      tempering: 550 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter 160 to 250 mm
      direction: transverse
      gauge: A5 as printed
      basis: minimum
      standard: DIN EN 10088-3
    method: A5 transverse column, +QT900 row, diameter 160 to 250 mm, printed as a plain number (minimum 14)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT900 row, 160 < d ≤ 250 (A5 in %, quer ≥ 14)
  - benchmark: charpy_impact_energy
    label: Impact energy AV, +QT900, diameter 160 to 250 mm, transverse (minimum)
    value: 60
    bound: lower
    unit: J
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      tempering: 550 to 620 C, water or air cooled (heat-treatment table)
      form: round product, diameter 160 to 250 mm
      direction: transverse
      test_temperature: not printed in this table
      basis: minimum
      standard: DIN EN 10088-3
    method: AV transverse column, +QT900 row, diameter 160 to 250 mm, printed as a plain number (minimum 60)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +QT900 row, 160 < d ≤ 250 (AV in J, quer ≥ 60)
  - benchmark: yield_strength
    label: Yield strength Rp0,2 at 100 C, +QT760 (minimum)
    value: 520
    bound: lower
    unit: MPa
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      tempering: 590 to 620 C, water or air cooled (heat-treatment table)
      temperature: 100 C
      form: not stated in the elevated-temperature table
      basis: minimum Rp0,2 at temperature
      standard: DIN EN 10088-3
    method: Elevated-temperature table, +QT760 row, 100 C column, Rp0,2 as printed (minimum 520)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei erhöhten Temperaturen im vergüteten Zustand (+QT) nach DIN EN 10088-3, +QT760 row, 100 C column (≥ 520)
  - benchmark: yield_strength
    label: Yield strength Rp0,2 at 200 C, +QT760 (minimum)
    value: 500
    bound: lower
    unit: MPa
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      tempering: 590 to 620 C, water or air cooled (heat-treatment table)
      temperature: 200 C
      form: not stated in the elevated-temperature table
      basis: minimum Rp0,2 at temperature
      standard: DIN EN 10088-3
    method: Elevated-temperature table, +QT760 row, 200 C column, Rp0,2 as printed (minimum 500)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei erhöhten Temperaturen im vergüteten Zustand (+QT) nach DIN EN 10088-3, +QT760 row, 200 C column (≥ 500)
  - benchmark: yield_strength
    label: Yield strength Rp0,2 at 300 C, +QT760 (minimum)
    value: 480
    bound: lower
    unit: MPa
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      tempering: 590 to 620 C, water or air cooled (heat-treatment table)
      temperature: 300 C
      form: not stated in the elevated-temperature table
      basis: minimum Rp0,2 at temperature
      standard: DIN EN 10088-3
    method: Elevated-temperature table, +QT760 row, 300 C column, Rp0,2 as printed (minimum 480)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei erhöhten Temperaturen im vergüteten Zustand (+QT) nach DIN EN 10088-3, +QT760 row, 300 C column (≥ 480)
  - benchmark: yield_strength
    label: Yield strength Rp0,2 at 100 C, +QT900 (minimum)
    value: 660
    bound: lower
    unit: MPa
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      tempering: 550 to 620 C, water or air cooled (heat-treatment table)
      temperature: 100 C
      form: not stated in the elevated-temperature table
      basis: minimum Rp0,2 at temperature
      standard: DIN EN 10088-3
    method: Elevated-temperature table, +QT900 row, 100 C column, Rp0,2 as printed (minimum 660)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei erhöhten Temperaturen im vergüteten Zustand (+QT) nach DIN EN 10088-3, +QT900 row, 100 C column (≥ 660)
  - benchmark: yield_strength
    label: Yield strength Rp0,2 at 200 C, +QT900 (minimum)
    value: 620
    bound: lower
    unit: MPa
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      tempering: 550 to 620 C, water or air cooled (heat-treatment table)
      temperature: 200 C
      form: not stated in the elevated-temperature table
      basis: minimum Rp0,2 at temperature
      standard: DIN EN 10088-3
    method: Elevated-temperature table, +QT900 row, 200 C column, Rp0,2 as printed (minimum 620)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei erhöhten Temperaturen im vergüteten Zustand (+QT) nach DIN EN 10088-3, +QT900 row, 200 C column (≥ 620)
  - benchmark: yield_strength
    label: Yield strength Rp0,2 at 300 C, +QT900 (minimum)
    value: 580
    bound: lower
    unit: MPa
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      tempering: 550 to 620 C, water or air cooled (heat-treatment table)
      temperature: 300 C
      form: not stated in the elevated-temperature table
      basis: minimum Rp0,2 at temperature
      standard: DIN EN 10088-3
    method: Elevated-temperature table, +QT900 row, 300 C column, Rp0,2 as printed (minimum 580)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei erhöhten Temperaturen im vergüteten Zustand (+QT) nach DIN EN 10088-3, +QT900 row, 300 C column (≥ 580)
  - benchmark: hardness
    label: Hardness, soft annealed +A, all diameters (maximum)
    value: 320
    bound: upper
    unit: HB
    scope: material
    conditions:
      condition: +A (soft annealed), all diameters
      basis: maximum
      standard: DIN EN 10088-3
    method: Room-temperature table, +A row, hardness as printed (maximum 320)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +A row (Härte in HB ≤ 320)
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, soft annealed +A, all diameters (maximum)
    value: 1100
    bound: upper
    unit: MPa
    scope: material
    conditions:
      condition: +A (soft annealed), all diameters
      basis: maximum
      standard: DIN EN 10088-3
    method: Room-temperature table, +A row, Rm as printed (maximum 1100)
    status: ground
    source: dew-1-4418-de
    where: Mechanische Eigenschaften bei Raumtemperatur im wärmebehandelten Zustand nach DIN EN 10088-3, +A row (Rm in MPa ≤ 1100)
  - benchmark: yield_strength
    label: Yield strength Rp0.2, +QT760, typical value (not a minimum)
    value: 820
    bound: exact
    unit: MPa
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      basis: typical column, not a minimum
      tempering: not printed on this sheet
      form: not stated on this sheet; sections of 160 mm and above are to be agreed
    method: Mechanical properties table, QT760 block, Typical column, Rp0.2 as printed (820)
    status: ground
    source: dew-1-4418-uk
    where: Mechanical properties table, QT760 block, Typical column (yield strength Rp0.2 820 N/mm2)
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, +QT760, typical value (not a minimum)
    value: 940
    bound: exact
    unit: MPa
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      basis: typical column, not a minimum
      tempering: not printed on this sheet
      form: not stated on this sheet; sections of 160 mm and above are to be agreed
    method: Mechanical properties table, QT760 block, Typical column, tensile strength as printed (940)
    status: ground
    source: dew-1-4418-uk
    where: Mechanical properties table, QT760 block, Typical column (tensile strength Rm 940 N/mm2)
  - benchmark: elongation
    label: Elongation A5, +QT760, typical value (not a minimum)
    value: 18
    bound: exact
    unit: '%'
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      gauge: A5 as printed
      basis: typical column, not a minimum
      tempering: not printed on this sheet
      form: not stated on this sheet; sections of 160 mm and above are to be agreed
    method: Mechanical properties table, QT760 block, Typical column, elongation as printed (18)
    status: ground
    source: dew-1-4418-uk
    where: Mechanical properties table, QT760 block, Typical column (elongation A5 18 %)
  - benchmark: yield_strength
    label: Yield strength Rp0.2, +QT900, typical value (not a minimum)
    value: 920
    bound: exact
    unit: MPa
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      basis: typical column, not a minimum
      tempering: not printed on this sheet
      form: not stated on this sheet; sections of 160 mm and above are to be agreed
    method: Mechanical properties table, QT900 block, Typical column, Rp0.2 as printed (920)
    status: ground
    source: dew-1-4418-uk
    where: Mechanical properties table, QT900 block, Typical column (yield strength Rp0.2 920 N/mm2)
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, +QT900, typical value (not a minimum)
    value: 1050
    bound: exact
    unit: MPa
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      basis: typical column, not a minimum
      tempering: not printed on this sheet
      form: not stated on this sheet; sections of 160 mm and above are to be agreed
    method: Mechanical properties table, QT900 block, Typical column, tensile strength as printed (1050)
    status: ground
    source: dew-1-4418-uk
    where: Mechanical properties table, QT900 block, Typical column (tensile strength Rm 1050 N/mm2)
  - benchmark: elongation
    label: Elongation A5, +QT900, typical value (not a minimum)
    value: 18
    bound: exact
    unit: '%'
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      gauge: A5 as printed
      basis: typical column, not a minimum
      tempering: not printed on this sheet
      form: not stated on this sheet; sections of 160 mm and above are to be agreed
    method: Mechanical properties table, QT900 block, Typical column, elongation as printed (18)
    status: ground
    source: dew-1-4418-uk
    where: Mechanical properties table, QT900 block, Typical column (elongation A5 18 %)
  - benchmark: charpy_impact_energy
    label: Impact energy ISO-V at 25 C, +QT760 (minimum)
    value: 90
    bound: lower
    unit: J
    scope: material
    conditions:
      condition: +QT760 (quenched and tempered, minimum tensile strength 760 MPa)
      test: ISO-V notch
      temperature: 25 C
      basis: minimum
      tempering: not printed on this sheet
    method: Mechanical properties table, QT760 block, impact energy row, 25 C ISO-V, minimum 90 as printed
    status: ground
    source: dew-1-4418-uk
    where: Mechanical properties table, QT760 block, impact energy (J) 25 C ISO-V ≥ 90
  - benchmark: charpy_impact_energy
    label: Impact energy ISO-V at 25 C, +QT900 (minimum)
    value: 80
    bound: lower
    unit: J
    scope: material
    conditions:
      condition: +QT900 (quenched and tempered, minimum tensile strength 900 MPa)
      test: ISO-V notch
      temperature: 25 C
      basis: minimum
      tempering: not printed on this sheet
    method: Mechanical properties table, QT900 block, impact energy row, 25 C ISO-V, minimum 80 as printed
    status: ground
    source: dew-1-4418-uk
    where: Mechanical properties table, QT900 block, impact energy (J) 25 C ISO-V ≥ 80
  - benchmark: density
    label: Density
    value: 7.7
    bound: exact
    unit: kg/dm3
    scope: material
    conditions:
      condition: not stated in the physical properties block
    method: Physical properties block, density row, printed as 7.70 kg/dm3
    status: ground
    source: dew-1-4418-uk
    where: Physical properties block, density (kg/dm3) 7.70
  - benchmark: thermal_conductivity
    label: Thermal conductivity at 20 C
    value: 15
    bound: exact
    unit: W/m K
    scope: material
    conditions:
      temperature: 20 C
    method: Physical properties block, thermal conductivity at 20 C in W/m K, printed as 15
    status: ground
    source: dew-1-4418-uk
    where: Physical properties block, thermal conductivity at 20 C (W/m K) 15
  - benchmark: specific_heat
    label: Specific heat capacity at 20 C
    value: 430
    bound: exact
    unit: J/kg K
    scope: material
    conditions:
      temperature: 20 C
    method: Physical properties block, specific heat capacity at 20 C in J/kg K, printed as 430
    status: ground
    source: dew-1-4418-uk
    where: Physical properties block, specific heat capacity at 20 C (J/kg K) 430
  - benchmark: cte
    label: Coefficient of thermal expansion, 20 to 100 C
    value: 10.8
    bound: exact
    unit: 10-6 K-1
    scope: material
    conditions:
      temperature_range: 20 to 100 C
    method: Physical properties block, thermal expansion row, 20 to 100 C, printed as 10.8 x 10-6 (K-1). The German sheet prints 10,3 for this range (see gaps)
    status: ground
    source: dew-1-4418-uk
    where: 'Physical properties block, thermal expansion (K-1), 20 - 100 C: 10.8 x 10-6'
  - benchmark: cte
    label: Coefficient of thermal expansion, 20 to 400 C
    value: 11.6
    bound: exact
    unit: 10-6 K-1
    scope: material
    conditions:
      temperature_range: 20 to 400 C
    method: Physical properties block, thermal expansion row, 20 to 400 C, printed as 11.6 x 10-6 (K-1)
    status: ground
    source: dew-1-4418-uk
    where: 'Physical properties block, thermal expansion (K-1), 20 - 400 C: 11.6 x 10-6'
  - benchmark: elastic_modulus
    label: Elastic modulus at 20 C
    value: 200
    bound: exact
    unit: GPa
    scope: material
    conditions:
      temperature: 20 C
    method: Physical properties block, E-Modul in GPa row, 20 C column, printed as 200
    status: ground
    source: dew-1-4418-de
    where: Physikalische Eigenschaften, E-Modul in GPa bei 20 °C (200)
  - benchmark: elastic_modulus
    label: Elastic modulus at 400 C
    value: 170
    bound: exact
    unit: GPa
    scope: material
    conditions:
      temperature: 400 C
    method: Physical properties block, E-Modul in GPa row, 400 C column, printed as 170
    status: ground
    source: dew-1-4418-de
    where: Physikalische Eigenschaften, E-Modul in GPa bei 400 °C (170)
  - benchmark: min_service_temp
    label: Lowest usable temperature (German sheet)
    value: -30
    bound: exact
    unit: °C
    scope: material
    conditions:
      condition: usable range as printed; no temper printed
    method: 'Besondere Eigenschaften text: suitable for temperatures between -30 C and 300 C'
    status: ground
    source: dew-1-4418-de
    where: Besondere Eigenschaften text (für den Einsatz bei Temperaturen zwischen -30°C und 300°C geeignet)
  - benchmark: max_service_temp
    label: Highest usable temperature (German sheet)
    value: 300
    bound: exact
    unit: °C
    scope: material
    conditions:
      condition: usable range as printed; no temper printed
    method: 'Besondere Eigenschaften text: suitable for temperatures up to 300 C'
    status: ground
    source: dew-1-4418-de
    where: Besondere Eigenschaften text (für den Einsatz bei Temperaturen zwischen -30°C und 300°C geeignet)
  - benchmark: max_service_temp
    label: Use temperature around 550 C (English sheet, approximate)
    value: 550
    bound: exact
    unit: °C
    scope: material
    conditions:
      condition: stated as around 550 C (approximate); no temper printed
    method: 'Special properties list: can be used to temperatures around 550 C. This conflicts with the German 300 C limit (see gaps)'
    status: ground
    source: dew-1-4418-uk
    where: Special properties list (can be used to temperatures around 550 °C)
corrosion:
  - environment: General corrosion resistance
    headline: Good (English sheet); gut (German sheet)
    effect: The English sheet rates corrosion resistance good, says 1.4418 is more resistant than 1.4057 because of its higher alloy content, and says molybdenum allows limited exposure to marine environments. It is extremely resistant to intergranular corrosion, corrosion fatigue and stress corrosion cracking.
    rating: low
    conditions:
      basis: DEW general statements, not test results
    source: dew-1-4418-uk
    where: General properties table (corrosion resistance good); corrosion resistance text
  - environment: Saturated sodium chloride at 20 C
    headline: Risk of pitting corrosion (DEW)
    effect: 'DEW table: NaCl saturated at 20 C gives ''Gefahr der Lochkorrosion'' (risk of pitting corrosion). DEW bases these figures on laboratory tests with pure agents and optimal specimens and calls them non-binding.'
    rating: moderate
    conditions:
      concentration: saturated
      temperature: 20 C
      basis: laboratory tests, pure agents, optimal specimens; non-binding
    source: dew-1-4418-de
    where: Korrosionsbeständigkeit table, NaCl row (Gefahr der Lochkorrosion)
  - environment: Sea water at 20 C
    headline: Risk of pitting corrosion (DEW)
    effect: DEW table gives 'Gefahr der Lochkorrosion' (risk of pitting corrosion) for sea water at 20 C. The English sheet says molybdenum allows limited exposure to marine environments.
    rating: moderate
    conditions:
      temperature: 20 C
      basis: laboratory tests, pure agents, optimal specimens; non-binding
    source: dew-1-4418-de
    where: Korrosionsbeständigkeit table, Meerwasser row (Gefahr der Lochkorrosion)
  - environment: Water vapour at 400 C
    headline: Resistant (DEW)
    effect: 'DEW table: water vapour at 400 C is ''beständig'' (resistant).'
    rating: low
    conditions:
      temperature: 400 C
      basis: laboratory tests, pure agents, optimal specimens; non-binding
    source: dew-1-4418-de
    where: Korrosionsbeständigkeit table, Wasserdampf row (beständig)
  - environment: Nitric acid, 7 percent, at 20 C
    headline: Resistant (DEW)
    effect: 'DEW table: nitric acid at 7 percent and 20 C is ''beständig'' (resistant).'
    rating: low
    conditions:
      concentration: 7 percent
      temperature: 20 C
      basis: laboratory tests, pure agents, optimal specimens; non-binding
    source: dew-1-4418-de
    where: Korrosionsbeständigkeit table, Salpetersäure row (beständig)
  - environment: Sulphuric acid, 1 percent, at 20 C
    headline: Resistant (DEW)
    effect: 'DEW table: sulphuric acid at 1 percent and 20 C is ''beständig'' (resistant).'
    rating: low
    conditions:
      concentration: 1 percent
      temperature: 20 C
      basis: laboratory tests, pure agents, optimal specimens; non-binding
    source: dew-1-4418-de
    where: Korrosionsbeständigkeit table, Schwefelsäure row (beständig)
  - environment: Formic acid, 10 percent, at 20 C
    headline: Resistant (DEW)
    effect: 'DEW table: formic acid at 10 percent and 20 C is ''beständig'' (resistant).'
    rating: low
    conditions:
      concentration: 10 percent
      temperature: 20 C
      basis: laboratory tests, pure agents, optimal specimens; non-binding
    source: dew-1-4418-de
    where: Korrosionsbeständigkeit table, Ameisensäure row (beständig)
  - environment: Intergranular corrosion, corrosion fatigue and stress corrosion cracking
    headline: Extremely resistant (English sheet)
    effect: The English sheet says 1.4418 is extremely resistant to intergranular corrosion, corrosion fatigue and stress corrosion cracking.
    rating: low
    source: dew-1-4418-uk
    where: Corrosion resistance text
  - environment: Pitting resistance index (PRE or PREN)
    headline: Printed as PRE 17.95 to 22.27 (English sheet)
    effect: The English sheet prints PRE = 17.95 to 22.27. The German sheet prints PREN = 17,9 to 22,3. Neither sheet prints the formula.
    rating: unknown
    source: dew-1-4418-uk
    where: Corrosion resistance heading (PRE = 17.95 - 22.27)
risks:
  hazards:
    - text: 'PubChem aggregated GHS for elemental nickel (CID 935): H317 and H351 under Warning, H372 under Danger, and H412 with no signal word in the record. PubChem describes these for the element, not for the 1.4418 alloy.'
      ghs:
        - H317
        - H351
        - H372
        - H412
      source: pubchem-nickel
      where: GHS Classification section, aggregated notifications (CID 935)
    - text: 'PubChem aggregated GHS for elemental chromium (CID 23976): H334 under Danger, H317 and H319 under Warning, with notified ratios of 20.3, 20.7 and 19.1 percent. PubChem says 50 percent of reports do not meet GHS criteria. These describe the element, not the alloy.'
      ghs:
        - H317
        - H319
        - H334
      source: pubchem-chromium
      where: GHS Classification section, aggregated notifications (CID 23976)
    - text: 'PubChem aggregated GHS for elemental molybdenum (CID 23932): H225 and H228 under Danger, H361, H315, H319 and H335 under Warning. PubChem says 57.4 percent of reports do not meet GHS criteria, and the codes vary by notification. These describe the element, not the alloy.'
      ghs:
        - H225
        - H228
        - H315
        - H319
        - H335
        - H361
      source: pubchem-molybdenum
      where: GHS Classification section, aggregated notifications (CID 23932)
  failure_risks:
    - mode: Pitting corrosion in chloride media
      trigger: Saturated sodium chloride or sea water at 20 C (DEW)
      consequence: 'DEW table: risk of pitting corrosion (Gefahr der Lochkorrosion) in both media'
      severity: moderate
      source: dew-1-4418-de
      where: Korrosionsbeständigkeit table, NaCl and Meerwasser rows
    - mode: Weld zone properties differ from the base metal
      trigger: Welding without heat treatment afterwards
      consequence: 'DEW: without additional heat treatment after welding, properties in the heat-affected zone and the weld can differ strongly from the base metal'
      severity: moderate
      source: dew-1-4418-de
      where: Schweißen text (Ohne eine zusätzliche Wärmenachbehandlung)
    - mode: Lower corrosion resistance from sulphur additions
      trigger: Sulphur added for machinability, up to 0,03 percent (German sheet)
      consequence: 'DEW: sulphur additions improve machinability but can negatively affect corrosion resistance and mechanical properties'
      severity: low
      source: dew-1-4418-de
      where: Spanende Bearbeitung text (Schwefelzusätze)
  side_effects: []
  handling:
    - text: 'Forging: heat gradually to about 800 C, then rapidly to 1150 to 1180 C, forge between 1180 and 950 C, and cool slowly in an oven or in dry ash (English sheet)'
      source: dew-1-4418-uk
      where: Forging paragraph
    - text: 'Forging: heat gradually above 800 C, then rapidly to 1150 to 1180 C, forge between 1180 and 950 C, then cool in air or in dry ash (German sheet)'
      source: dew-1-4418-de
      where: Schmieden text and Warmumformung table (1150 - 900, Luft)
    - text: Hardening at 1000 to 1050 C, cooled in air, oil or polymer (English sheet)
      source: dew-1-4418-uk
      where: Heat treatment paragraph
    - text: Hardening window 950 to 1050 C with polymer, oil or air (German sheet)
      source: dew-1-4418-de
      where: Wärmebehandlung table, Härten row
    - text: Soft annealing at about 600 C, not above 625 C, then slow cooling in air (English sheet)
      source: dew-1-4418-uk
      where: Heat treatment paragraph
    - text: 'Tempering: QT760 at 590 to 620 C and QT900 at 550 to 620 C, water or air cooled (German sheet)'
      source: dew-1-4418-de
      where: Wärmebehandlung table, Anlassen rows
    - text: 'Tempering: pass the range from 420 to 510 C rapidly, and cool the steel to below 40 C before the final tempering (English sheet)'
      source: dew-1-4418-uk
      where: Heat treatment note
    - text: 'Machining: similar to structural steel of the same hardness; drilling 20 to 60 m/min, turning 35 to 95 m/min, milling 80 to 175 m/min (German sheet)'
      source: dew-1-4418-de
      where: Spanende Bearbeitung text and Schnittbedingungen table
    - text: Cold forming is possible and cold heading is not common (English and German sheets)
      source: dew-1-4418-uk
      where: Processing properties table (cold forming yes; cold heading not common)
    - text: 'Suited to polishing (English sheet; German sheet: polierfähig ja)'
      source: dew-1-4418-uk
      where: Processing properties table (suited to polishing yes)
  mitigations:
    - text: Preheat to 100 to 200 C before welding (German sheet, below the Ms temperature; English sheet, the same range)
      source: dew-1-4418-de
      where: Schweißen text
    - text: Anneal or temper after welding (both sheets)
      source: dew-1-4418-de
      where: Schweißen text
    - text: Use a matching filler or Novonit 4430 (English sheet); the German sheet names filler 1.4430
      source: dew-1-4418-uk
      where: Welding paragraph
    - text: Avoid hydrogen- or nitrogen-containing shielding gases (German sheet) and hydrogen- or carbon-containing gases (English sheet)
      source: dew-1-4418-de
      where: Schweißen text (wasserstoff- oder stickstoffhaltiger Gase)
uses:
  - application: structures
    device: Aviation and aerospace parts (no part named)
    example: 'Both sheets list aviation and aerospace as an application (German sheet: Luft- und Raumfahrtindustrie). No spacecraft part is named.'
    source: dew-1-4418-uk
    where: Typical applications list (English); Anwendungsgebiete list (German)
  - application: mechanisms
    device: Shafts and axles
    example: 'German sheet: mechanically and corrosively loaded parts such as shafts (Wellen) and axles (Achsen) in the automotive, chemical, aerospace and machinery industries'
    source: dew-1-4418-de
    where: Verwendungshinweise text
  - application: mechanisms
    device: Pump and centrifuge parts
    example: 'German sheet: centrifuge parts (Zentrifugenteile) and pump parts (Pumpenteile) in the same list of uses'
    source: dew-1-4418-de
    where: Verwendungshinweise text
supply:
  - subject: Chromium production by country
    abundance: World mine production 51,000 thousand t gross weight in 2025 (estimated; 49,600 thousand t in 2024). World resources greater than 12 billion t of shipping-grade chromite, 95 percent in Kazakhstan and southern Africa (USGS MCS 2026). Shares computed from the printed 2025 gross-weight tonnages.
    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
      - country: Brazil
        share_percent: 3.9
        year: 2025
      - country: Zimbabwe
        share_percent: 3.9
        year: 2025
    critical_lists: []
    recycling: Recycled chromium in reported stainless-steel scrap receipts was 21 percent of apparent consumption in 2025 (USGS MCS 2026).
    substitutes:
      - Chromium has no substitute in stainless steel, the leading end use, or in superalloys (USGS MCS 2026).
    source: usgs-chromium-2026
    where: World Mine Production and Reserves table; Recycling; Substitutes
  - subject: Chromium import reliance
    abundance: 'US net import reliance was 79 percent of apparent consumption in 2025 (estimated). Chromite imports 2021 to 2024: South Africa 96 percent, Turkey 3 percent, other 1 percent (USGS MCS 2026).'
    producers: []
    critical_lists: []
    substitutes: []
    source: usgs-chromium-2026
    where: Salient Statistics (net import reliance row); Import Sources (2021-24)
  - subject: Nickel production by country
    abundance: World mine production 3,900,000 t of nickel content in 2025 (estimated; 3,710,000 t in 2024). World reserves more than 140,000,000 t, of which Indonesia 62,000,000 t (USGS MCS 2026). Shares computed from the printed 2025 tonnages.
    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
      - country: China
        share_percent: 3.1
        year: 2025
    critical_lists: []
    recycling: Nickel recovered from scrap was about 60 percent of US apparent consumption in 2025; most secondary nickel is the nickel content of stainless-steel scrap (USGS MCS 2026).
    substitutes:
      - Nickel-free specialty steels are sometimes used in place of stainless steel in the power-generating and petrochemical industries (USGS MCS 2026).
      - Low-nickel, duplex or ultrahigh-chromium stainless steels have been substituted for austenitic grades in construction (USGS MCS 2026).
    source: usgs-nickel-2026
    where: World Mine Production and Reserves table; Recycling; Substitutes
  - subject: Nickel use, US import reliance and critical-mineral policy
    abundance: Stainless and alloy steel and nickel-containing alloys typically account for more than 85 percent of US domestic consumption. US net import reliance was 41 percent of apparent consumption in 2025 (estimated). The page notes Executive Order 14285 (April 2025) on seabed minerals to help secure critical minerals such as nickel, but prints no critical-mineral list (USGS MCS 2026).
    producers: []
    critical_lists: []
    substitutes: []
    source: usgs-nickel-2026
    where: Domestic Production and Use; Salient Statistics (net import reliance row); Events, Trends, and Issues
  - subject: Molybdenum production by country
    abundance: World mine production 260,000 t of molybdenum content in 2025 (estimated; 256,000 t in 2024). World reserves 17,000 thousand t (USGS MCS 2026). China imposed export controls on molybdenum powders in February 2025, and the United States is a net exporter (E) of molybdenum. Shares computed from the printed 2025 tonnages.
    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: []
    recycling: Molybdenum recycled as part of new and old steel and other scrap may be as much as 30 percent of apparent supply (USGS MCS 2026).
    substitutes:
      - There is little substitution for molybdenum in steels and cast irons. Potential substitutes include boron, chromium, niobium and vanadium in alloy steels (USGS MCS 2026).
    source: usgs-molybdenum-2026
    where: World Mine Production and Reserves table; Events, Trends, and Issues; Recycling; Substitutes
media: []
documents:
  - title: 'Deutsche Edelstahlwerke (Swiss Steel Group): 1.4418 X4CrNiMo16-5-1 datasheet, English (Revision-No. 4418-1)'
    type: datasheet
    url: https://swisssteel-group.com/content-media/documents/Data-Sheets/Stainless-Steel/Datenblatt_4418_UK.pdf
  - title: 'Deutsche Edelstahlwerke: Acidur 4418 Werkstoffdatenblatt, X4CrNiMo16-5-1, 1.4418 (datasheet 2015-0028)'
    type: datasheet
    url: https://swisssteel-group.com/content-media/documents/Data-Sheets/Stainless-Steel/1.4418_de.pdf
    year: 2015
  - 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: 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: 'PubChem: Nickel (CID 935), UN GHS classification'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/935/JSON
  - title: 'PubChem: Chromium (CID 23976), UN GHS classification'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23976/JSON
  - title: 'PubChem: Molybdenum (CID 23932), GHS classification'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23932/JSON
gaps:
  - Web search was unavailable in this run (its budget was used up), so the datasheets, USGS reports and PubChem records were fetched directly. No ASTM, JIS, AISI, UNS or other cross-reference for 1.4418 is printed on any page read, so none is listed.
  - No UNS number is printed on the 1.4418 sheets. UNS S41500 is a different grade (13Cr-4Ni, EN 1.4313), and no value or designation from that grade was used.
  - The German sheet's standards table prints AIR9160C beside the name Z8CND17-04. The table does not say which grade the standard covers, so it is not listed as a designation. It also prints DIN EN 10250-4 with no code, so that is not listed either.
  - 'The two DEW sheets disagree: the English sheet (Revision-No. 4418-1) gives hardening at 1000 to 1050 C, a use limit around 550 C and cryogenic use, while the German sheet (2015-0028) gives 950 to 1050 C and -30 to 300 C. Both are kept, each with its own source.'
  - Electrical resistivity is printed as 0.70 (unit Ω mm2/m) on the English sheet and as 0,8 on the German sheet. The unit is not in the unit registry and the German value has a decimal comma, so it is not in the properties.
  - The German sheet's decimal-comma values (density 7,7; mean thermal expansion 10,3 at 20 to 100 C) are not in the properties because the gate cannot match decimal commas. The English sheet gives 10.8 for 20 to 100 C, which conflicts with the German 10,3.
  - The 160 to 250 mm rows repeat the Rp0,2 and tensile values of the 160 mm rows. Only the transverse elongation and impact values differ, and those are recorded.
  - Elevated-temperature Rp0,2 values at 150 and 250 C are printed in the German table but are not recorded. The English sheet gives only a diagram without numbers.
  - Hardness and charpy_impact_energy are not in spores/property-canon.yaml, so short snake_case names are used. The English typical values are recorded as typical, not as minimums.
  - No melting point, fracture toughness, fatigue strength, sour-service (NACE) limit or hydrogen-cracking limit is printed on the fetched pages. The English sheet says the grade is ferromagnetic and the German sheet says magnetisable (vorhanden), with no number.
  - The English sheet's typical values carry no tempering temperature and no product size. The German table gives tempering ranges but no typical values.
  - 'The corrosion figures are laboratory data with pure agents and optimal specimens, which DEW calls non-binding. Ratings map DEW''s words: beständig to low and Gefahr der Lochkorrosion to moderate.'
  - Failure-risk severities are the assistant's ratings; the sources give none.
  - Hazards are PubChem element records for nickel, chromium and molybdenum, not supplier classifications of the alloy. No safety data sheet for 1.4418 was read.
  - No space, flight, radiation or NASA or ESA source naming 1.4418 was read. The aerospace use is named only as a general application.
  - The USGS chromium, nickel and molybdenum texts print no critical-mineral list, so critical_lists is empty. Producer shares are computed from the printed tonnages.
  - The sheets name no equivalent grade. Acidur 4418 is DEW's own trade name for this grade.
sources:
  dew-1-4418-uk:
    title: 'Deutsche Edelstahlwerke (Swiss Steel Group): 1.4418 X4CrNiMo16-5-1 datasheet, English'
    id: Revision-No. 4418-1
    url: https://swisssteel-group.com/content-media/documents/Data-Sheets/Stainless-Steel/Datenblatt_4418_UK.pdf
    kind: datasheet
    license: cited, not reproduced
  dew-1-4418-de:
    title: 'Deutsche Edelstahlwerke: Acidur 4418 Werkstoffdatenblatt, X4CrNiMo16-5-1, 1.4418'
    id: 2015-0028
    url: https://swisssteel-group.com/content-media/documents/Data-Sheets/Stainless-Steel/1.4418_de.pdf
    kind: datasheet
    year: 2015
    license: cited, not reproduced
  usgs-chromium-2026:
    title: 'USGS Mineral Commodity Summaries 2026: Chromium'
    id: mcs2026-chromium
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-chromium.pdf
    kind: report
    year: 2026
    license: public domain
  usgs-nickel-2026:
    title: 'USGS Mineral Commodity Summaries 2026: Nickel'
    id: mcs2026-nickel
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-nickel.pdf
    kind: report
    year: 2026
    license: public domain
  usgs-molybdenum-2026:
    title: 'USGS Mineral Commodity Summaries 2026: Molybdenum'
    id: mcs2026-molybdenum
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-molybdenum.pdf
    kind: report
    year: 2026
    license: public domain
  pubchem-nickel:
    title: 'PubChem: Nickel (CID 935), UN GHS classification'
    id: CID 935
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/935/JSON
    kind: database
    license: PubChem terms (public)
  pubchem-chromium:
    title: 'PubChem: Chromium (CID 23976), UN GHS classification'
    id: CID 23976
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23976/JSON
    kind: database
    license: PubChem terms (public)
  pubchem-molybdenum:
    title: 'PubChem: Molybdenum (CID 23932), GHS classification'
    id: CID 23932
    url: https://pubchem.ncbi.nlm.nih.gov/rest/pug_view/data/compound/23932/JSON
    kind: database
    license: PubChem terms (public)
license: CC-BY-4.0
updated: '2026-10-24'
review:
  status: draft
  method: assistant
  checked_values: 38
  unreachable: 0
  caveats: 4
  note: 'Written by an AI assistant on 2026-10-24 from pages fetched in this run: the two DEW 1.4418 datasheets (English Revision-No. 4418-1 and German 2015-0028), USGS MCS 2026 chromium, nickel and molybdenum, and PubChem nickel, chromium and molybdenum. Web search was unavailable, so the pages were fetched directly. Caveats: the DEW sheets disagree on hardening, service range, thermal expansion from 20 to 100 C and electrical resistivity; the English typical values carry no tempering temperature.'
story:
  why: EN 1.4418 (X4CrNiMo16-5-1) is a soft martensitic stainless steel with 15.00 to 17.00 percent chromium, 4.00 to 6.00 percent nickel and 0.80 to 1.50 percent molybdenum. Deutsche Edelstahlwerke sells it as Acidur 4418, quenches and tempers it to QT760 or QT900, and lists shafts, axles, pump and centrifuge parts, the chemical industry, shipbuilding and aviation and aerospace among its uses.
  uses:
    - where: Aviation and aerospace
      line: Both sheets list aviation and aerospace as an application, and the German sheet names the aerospace industry. No spacecraft part is named.
    - where: Shafts, axles, pumps and centrifuges
      line: The German sheet lists mechanically and corrosively loaded shafts, axles, centrifuge parts and pump parts.
    - where: Chemical industry and shipbuilding
      line: Both sheets list the chemical industry, mechanical engineering, aerospace and shipbuilding. The German sheet also lists the automotive industry.
  can_do:
    - label: Strength
      line: Quenched and tempered to QT760, the German sheet gives at least 550 MPa yield and 760 to 960 MPa tensile strength for sections up to 160 mm. QT900 gives at least 700 MPa yield and 900 to 1100 MPa tensile strength.
    - label: Toughness
      line: The English sheet gives at least 90 J for QT760 and 80 J for QT900 at 25 C in ISO-V impact tests. The German sheet gives at least 90 J longitudinal for QT760 up to 160 mm.
    - label: Hot strength
      line: The German sheet gives a minimum yield strength at 300 C of 480 MPa for QT760 and 580 MPa for QT900.
    - label: Low temperature
      line: The German sheet gives -30 C as the low end of use. The English sheet says the grade can be used in cryogenic applications.
    - label: Stiffness
      line: The German sheet gives an elastic modulus of 200 GPa at 20 C and 170 GPa at 400 C.
    - label: Corrosion
      line: The English sheet rates general corrosion resistance good and says molybdenum allows limited marine exposure.
  compare: The two DEW sheets differ on several figures. The English sheet (Revision-No. 4418-1) gives hardening at 1000 to 1050 C, a use limit around 550 C and cryogenic use, while the German sheet (2015-0028) gives 950 to 1050 C and -30 to 300 C. The English sheet says 1.4418 is more resistant to corrosion than 1.4057. The German sheet rates the PREN at 17,9 to 22,3, and the English sheet prints PRE 17.95 to 22.27. No page for another stainless grade was fetched in this run, so no numeric comparison with other grades is made.
  compare_rows:
    - label: Yield strength (QT760 minimum)
      benchmark: yield_strength
      scope: material
    - label: Tensile strength (QT760 range)
      benchmark: ultimate_tensile_strength
      scope: material
    - label: Density
      benchmark: density
      scope: material
  handling:
    - Forge after heating gradually to about 800 C, then heat quickly to 1150 to 1180 C, forge between 1180 and 950 C, and cool slowly in an oven or in dry ash (both sheets).
    - Preheat to 100 to 200 C before welding, and anneal or temper after welding (both sheets).
    - Harden at 1000 to 1050 C (English sheet) or 950 to 1050 C (German sheet), then temper at 590 to 620 C for QT760 or 550 to 620 C for QT900 (German sheet).
    - Cold forming is possible and cold heading is not common (both sheets).
  good_for:
    - Shafts, axles, pump and centrifuge parts that need quenched and tempered strength with good toughness (DEW).
    - Chemical, marine-exposed and aerospace parts where good general corrosion resistance is needed (DEW).
    - Parts used down to -30 C (German sheet) or in cryogenic applications (English sheet).
  watch_out:
    - 'Chlorides: DEW gives a risk of pitting corrosion in saturated sodium chloride and in sea water at 20 C.'
    - 'Welding: without heat treatment after welding, the heat-affected zone and the weld can differ strongly from the base metal (German sheet).'
    - The two DEW sheets disagree on hardening, the service range and the electrical resistivity, so check the revision before design.
    - Sulphur additions for machinability can lower corrosion resistance (German sheet).
  verdict: EN 1.4418 (X4CrNiMo16-5-1) is a quenched and tempered, corrosion-resistant martensitic steel. DEW sells it for shafts, axles, pump and centrifuge parts and lists aviation and aerospace use. Its strength levels and impact values are sourced. Its limits are pitting in chloride media, weld properties that depend on heat treatment after welding, and two DEW revisions that disagree on several figures. No space-environment, flight or NASA data for 1.4418 were found.
  recipe:
    line: 'EN 1.4418 is an iron-based martensitic stainless steel with chromium, nickel and molybdenum and low carbon. Composition limits are in mass percent (German sheet: in Massen-% nach DIN EN 10088-3). The steel is supplied annealed, or hardened and tempered to QT760 or QT900.'
    parts:
      - name: Iron
        symbol: Fe
        share_note: balance (the rest)
        role: Matrix of the alloy; the English sheet calls it a soft martensitic steel
        source: dew-1-4418-uk
        where: Title block
      - name: Chromium
        symbol: Cr
        share_percent: 15
        share_high: 17
        role: Stainless element for corrosion resistance (general chemistry; the limits are on the sheet)
        source: dew-1-4418-uk
        where: Title block, Cr 15.00 - 17.00
      - name: Nickel
        symbol: Ni
        share_percent: 4
        share_high: 6
        role: Alloying element (the limits are on the sheet)
        source: dew-1-4418-uk
        where: Title block, Ni 4.00 - 6.00
      - name: Molybdenum
        symbol: Mo
        share_percent: 0.8
        share_high: 1.5
        role: Alloying element; the English sheet says molybdenum allows limited marine exposure
        source: dew-1-4418-uk
        where: Title block, Mo 0.80 - 1.50
      - name: Carbon
        symbol: C
        share_note: max 0.06
        role: Kept low
        source: dew-1-4418-uk
        where: Title block, C max. 0.06
      - name: Nitrogen
        symbol: 'N'
        share_note: min 0.02
        role: Added nitrogen
        source: dew-1-4418-uk
        where: Title block, N >= 0.02
      - name: Silicon
        symbol: Si
        share_note: max 0.7
        role: Melt element, held to a maximum
        source: dew-1-4418-de
        where: Chemische Zusammensetzung table, Si max 0,7
      - name: Manganese
        symbol: Mn
        share_note: max 1.5
        role: Melt element, held to a maximum
        source: dew-1-4418-de
        where: Chemische Zusammensetzung table, Mn max 1,5
      - name: Phosphorus
        symbol: P
        share_note: max 0.04
        role: Impurity held low
        source: dew-1-4418-de
        where: Chemische Zusammensetzung table, P max 0,04
      - name: Sulphur
        symbol: S
        share_note: max 0.03
        role: Impurity held low; up to this amount may be added for machinability (German sheet)
        source: dew-1-4418-de
        where: Chemische Zusammensetzung table, S max 0,03; Spanende Bearbeitung text
  risk_groups:
    - title: For people
      level: 1
      verdict: PubChem element records only; no SDS read
      lead: The PubChem records below describe elemental nickel, chromium and molybdenum. No safety data sheet for 1.4418 was read.
      points:
        - label: Nickel
          line: PubChem lists H317, H351, H372 and H412 for elemental nickel.
        - label: Chromium
          line: PubChem lists H317, H319 and H334 for elemental chromium.
        - label: Molybdenum
          line: PubChem lists H225, H228, H315, H319, H335 and H361 for elemental molybdenum, from notifications that vary.
    - title: In the environment
      level: 2
      verdict: Chlorides are the main watch point
      lead: Pitting in chloride water is the main limit in service. The German sheet rates the listed acids resistant.
      points:
        - label: Chloride
          line: DEW gives a risk of pitting corrosion in saturated sodium chloride and in sea water at 20 C.
        - label: Acids
          line: DEW rates 7 percent nitric acid, 1 percent sulphuric acid and 10 percent formic acid at 20 C as resistant.
    - title: Welding and heat
      level: 2
      verdict: Preheat, then heat-treat after welding
      lead: Welding needs preheat and heat treatment afterwards to keep the weld close to the base metal.
      points:
        - label: Preheat
          line: Preheat to 100 to 200 C before welding (both sheets).
        - label: After welding
          line: Anneal or temper after welding (both sheets).