Aluminium casting alloy A356.0 A356

spore: profile
id: aluminium-a356
spore_version: 0.2
family: aluminium-alloys
name: Aluminium casting alloy A356.0
abbreviation: A356
role: structural casting alloy
category: metals
type: aluminium
summary: |
  A356.0 is an aluminium-silicon-magnesium casting alloy, UNS A13560. The Xometry datasheet gives 6.5 to 7.5 % silicon and 0.25 to 0.45 % magnesium, a density of 2.68 g/cm3, and a T6 permanent-mould tensile strength of 276 to 345 MPa. NIMS and JAXA issued strength data sheets for cast A356-T6 as a space-use material for Japan's H-IIA and H-IIB rockets.
best_for: Thin, complex castings that need good fluidity and a heat-treated strength of 276 to 345 MPa (T6, permanent mould, datasheet)
weakest_at: 'Ductility: elongation of 5 to 12 % in T6 permanent-mould castings and 3 to 10 % in T6 sand castings (datasheet)'
identity:
  formula: 'Al-Si-Mg casting alloy, mass %: Al balance, Si 6.5-7.5, Mg 0.25-0.45, Fe max 0.20, Cu max 0.20, Zn max 0.10, Mn max 0.10, Ti max 0.20 (datasheet composition table)'
  cas: 7429-90-5
  source: xometry-a356
  where: Chemical composition table, section 1 of the Xometry A356 datasheet. CAS 7429-90-5 is the aluminium element number printed on the Total Materia UNS A13560 page; the alloy itself has no CAS number.
  designations:
    - system: UNS
      code: A13560
      source: totalmat-a13560
      where: Page heading UNS A13560 Aluminium Alloys
    - system: AA
      code: A356.0
      source: totalmat-a13560
      where: International Equivalent Materials list, row AA A356.0
    - system: SAE
      code: A13560
      source: totalmat-a13560
      where: International Equivalent Materials list, row A13560 (SAE)
    - system: AMS
      code: AMS4218
      note: premium grade 7Si - 0.3Mg (A356)
      source: ams4218
      where: Specification title and revision list
    - system: ASTM
      code: B26
      source: totalmat-a13560
      where: International Equivalent Materials list, row B 26 A356.0
    - system: ASTM
      code: B108
      source: totalmat-a13560
      where: International Equivalent Materials list, row B 108 A356.0
tags:
  environments: []
  stresses: []
  applications:
    - structures
properties:
  - benchmark: density
    label: Density, A356 casting alloy
    value: 2.68
    unit: g/cm3
    scope: material
    conditions:
      alloy: A356 casting alloy
      temper: not stated in the table
      unit_in_source: 0.097 lb/in3
    method: Value printed in the Xometry A356 datasheet, which states its data come from OEMs, distributors and databases
    status: ground
    source: xometry-a356
    where: Section 2, Physical properties table, row Density
  - benchmark: density
    label: Density, UNS A13560 (Total Materia range)
    value: 2.6
    value_high: 2.9
    bound: range
    unit: kg/dm3
    scope: material
    conditions:
      temperature: 0 - 30 °C
      designation: UNS A13560
    method: Range printed on the Total Materia physical properties table for UNS A13560
    status: ground
    note: Wider than the single datasheet value of 2.68 g/cm3; the two sources are shown side by side.
    source: totalmat-a13560
    where: UNS A13560 Physical Properties, row Density
  - benchmark: melting_point
    label: Melting range (solidus to liquidus)
    value: 557
    value_high: 613
    bound: range
    unit: °C
    scope: material
    conditions:
      basis: solidus to liquidus range, printed as Melting range
      alloy: A356 casting alloy
    method: Range printed in the Xometry A356 datasheet; a melting range, not a single melting point
    status: ground
    source: xometry-a356
    where: Section 2, Physical properties table, row Melting range
  - benchmark: thermal_conductivity
    label: Thermal conductivity, T6 temper
    value: 149
    value_high: 155
    bound: range
    unit: W/(m·K)
    scope: material
    conditions:
      temper: T6
      temperature: not stated in the table
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 2, Physical properties table, row Thermal conductivity (T6 temper)
  - benchmark: electrical_conductivity
    label: Electrical conductivity
    value: 33
    value_high: 40
    bound: range
    unit: '%IACS'
    scope: material
    conditions:
      temper: not stated in the table
    method: Range printed in the Xometry A356 datasheet; the datasheet calls it moderate electrical conductivity
    status: ground
    source: xometry-a356
    where: Section 2, Physical properties table, row Electrical conductivity
  - benchmark: elastic_modulus
    label: Elastic modulus, Xometry datasheet
    value: 72.4
    unit: GPa
    scope: material
    conditions:
      temperature: not stated in the table
    method: Value printed in the Xometry A356 datasheet
    status: ground
    note: Total Materia gives a wider range of 69 to 79 GPa for the same UNS number; both are kept.
    source: xometry-a356
    where: Section 2, Physical properties table, row Elastic modulus
  - benchmark: elastic_modulus
    label: Elastic modulus, UNS A13560 (Total Materia range)
    value: 69
    value_high: 79
    bound: range
    unit: GPa
    scope: material
    conditions:
      temperature: 0 - 30 °C
      designation: UNS A13560
    method: Range printed on the Total Materia physical properties table for UNS A13560
    status: ground
    source: totalmat-a13560
    where: UNS A13560 Physical Properties, row Modulus of Elasticity
  - benchmark: poissons_ratio
    label: Poisson's ratio
    value: 0.33
    unit: '-'
    scope: material
    conditions:
      temperature: not stated in the table
    method: Value printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 2, Physical properties table, row Poisson's ratio
  - benchmark: specific_heat
    label: Specific heat capacity at 20 °C
    value: 963
    unit: J/(kg·K)
    scope: material
    conditions:
      temperature: 20 °C
      unit_in_source: 0.230 Btu/(lb·°F)
    method: Value printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 2, Physical properties table, row Specific heat capacity
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, T6 permanent mould
    value: 276
    value_high: 345
    bound: range
    unit: MPa
    scope: material
    conditions:
      temper: T6
      casting: permanent mould
      unit_in_source: 276-345 MPa
    method: Range printed in the Xometry A356 datasheet, mechanical properties by heat treatment condition
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Tensile strength, column T6 temper (permanent mold)
  - benchmark: ultimate_tensile_strength
    label: Tensile strength, T6 sand cast
    value: 234
    value_high: 310
    bound: range
    unit: MPa
    scope: material
    conditions:
      temper: T6
      casting: sand cast
      unit_in_source: 234-310 MPa
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Tensile strength, column T6 temper (sand cast)
  - benchmark: yield_strength
    label: Yield strength, T6 permanent mould
    value: 207
    value_high: 276
    bound: range
    unit: MPa
    scope: material
    conditions:
      temper: T6
      casting: permanent mould
      offset: not stated in the datasheet
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Yield strength, column T6 temper (permanent mold)
  - benchmark: yield_strength
    label: Yield strength, T6 sand cast
    value: 165
    value_high: 234
    bound: range
    unit: MPa
    scope: material
    conditions:
      temper: T6
      casting: sand cast
      offset: not stated in the datasheet
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Yield strength, column T6 temper (sand cast)
  - benchmark: elongation
    label: Elongation, T6 permanent mould
    value: 5
    value_high: 12
    bound: range
    unit: '%'
    scope: material
    conditions:
      temper: T6
      casting: permanent mould
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Elongation, column T6 temper (permanent mold)
  - benchmark: elongation
    label: Elongation, T6 sand cast
    value: 3
    value_high: 10
    bound: range
    unit: '%'
    scope: material
    conditions:
      temper: T6
      casting: sand cast
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Elongation, column T6 temper (sand cast)
  - benchmark: brinell_hardness
    label: Brinell hardness, T6 permanent mould
    value: 80
    value_high: 100
    bound: range
    unit: HB
    scope: material
    conditions:
      temper: T6
      casting: permanent mould
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Brinell Hardness HB, column T6 temper (permanent mold)
  - benchmark: fatigue_strength
    label: Fatigue strength at 10 million cycles, T6 permanent mould
    value: 100
    value_high: 125
    bound: range
    unit: MPa
    scope: material
    conditions:
      temper: T6
      casting: permanent mould
      cycles: 10 million
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Fatigue strength (10 7 cycles), column T6 temper (permanent mold)
  - benchmark: shear_strength
    label: Shear strength, T6 permanent mould
    value: 186
    value_high: 207
    bound: range
    unit: MPa
    scope: material
    conditions:
      temper: T6
      casting: permanent mould
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Shear strength, column T6 temper (permanent mold)
  - benchmark: fracture_toughness
    label: Fracture toughness K_IC, T6 permanent mould
    value: 25
    value_high: 32
    bound: range
    unit: MPa√m
    scope: material
    conditions:
      temper: T6
      casting: permanent mould
      test: K_IC as labelled in the datasheet
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Fracture toughness K_IC, column T6 temper (permanent mold)
  - benchmark: charpy_impact_energy
    label: Charpy impact toughness, T6 permanent mould
    value: 12
    value_high: 18
    bound: range
    unit: J
    scope: material
    conditions:
      temper: T6
      casting: permanent mould
      test: Charpy impact as labelled in the datasheet
    method: Range printed in the Xometry A356 datasheet
    status: ground
    source: xometry-a356
    where: Section 3, Mechanical properties table, row Impact toughness (Charpy), column T6 temper (permanent mold)
  - benchmark: vickers_hardness
    label: Vickers hardness, as-cast
    value: 58.6
    unit: HV
    scope: material
    conditions:
      temper: as-cast
      load: 150 gf
      dwell: 15 s
      alloy: laboratory casting, composition in Table 1 of the paper
    method: Vickers hardness as printed in the Section 3.2 table, row As-cast
    status: ground
    note: Laboratory casting, not the datasheet grade. The Si and Mg content sits inside the datasheet ranges at its upper end.
    source: jang-2025-corrosion
    where: Section 3.2, Vickers hardness table, row As-cast
  - benchmark: vickers_hardness
    label: Vickers hardness, solution-treated and aged 9 h at 190 °C
    value: 92.8
    unit: HV
    scope: material
    conditions:
      temper: solution treated at 525 °C for 4 h, aged at 190 °C for 9 h
      load: 150 gf
      dwell: 15 s
      alloy: laboratory casting, composition in Table 1 of the paper
    method: Vickers hardness as printed in the Section 3.2 table, row SA9
    status: ground
    note: The paper's Summary section gives a slightly different figure for this condition. The Section 3.2 table value is used here.
    source: jang-2025-corrosion
    where: Section 3.2, Vickers hardness table, row Aged 9 h (SA9)
  - benchmark: corrosion_current_density
    label: Corrosion current density, as-cast, 3.5 wt.% NaCl
    value: 0.5
    unit: μA/cm²
    scope: material
    conditions:
      electrolyte: 3.5 wt.% NaCl
      temper: as-cast
      alloy: laboratory casting, composition in Table 1 of the paper
    method: Icorr from the polarization test as printed in Table 3, row As-cast, shown as a mean with a standard deviation
    status: ground
    note: Laboratory test on a casting, not a datasheet grade. The table gives a standard deviation that is left out here.
    source: jang-2025-corrosion
    where: Table 3, row As-cast, column Icorr
  - benchmark: corrosion_current_density
    label: Corrosion current density, aged 9 h at 190 °C, 3.5 wt.% NaCl
    value: 1.89
    unit: μA/cm²
    scope: material
    conditions:
      electrolyte: 3.5 wt.% NaCl
      temper: solution treated at 525 °C for 4 h, aged at 190 °C for 9 h
      alloy: laboratory casting, composition in Table 1 of the paper
    method: Icorr from the polarization test as printed in Table 3, row SA9, shown as a mean with a standard deviation
    status: ground
    note: Laboratory test on a casting, not a datasheet grade. The table gives a standard deviation that is left out here.
    source: jang-2025-corrosion
    where: Table 3, row SA9, column Icorr
corrosion:
  - environment: Atmospheric and seawater exposure, as a manufacturer statement
    headline: Xometry says A356 resists atmospheric and seawater corrosion, but gives no test conditions or rates.
    effect: The datasheet says the alloy easily forms an oxide film and is resistant to atmospheric and seawater corrosion. It gives no exposure time, test standard or corrosion rate, so this rating is qualitative only.
    rating: low
    conditions:
      basis: qualitative statement in the datasheet summary
      test: none given
    source: xometry-a356
    where: Section 6, Summary of key features (Good corrosion resistance)
  - environment: Impurities above the composition limits
    headline: Excess impurities, including copper, may reduce corrosion resistance, according to the datasheet.
    effect: The composition table lists copper at 0.20 % or less and notes that excessive amounts of impurities may reduce corrosion resistance. No corrosion rate is given for a higher copper content.
    rating: unknown
    conditions:
      basis: composition note in the datasheet
      test: none given
    source: xometry-a356
    where: Section 1, Chemical composition table, row Copper
  - environment: 3.5 wt.% NaCl solution, laboratory polarization test on a cast A356 specimen
    headline: In a laboratory 3.5 wt.% NaCl test, the corrosion current density of as-cast A356 is 0.50 μA/cm², and it is 1.89 μA/cm² after 9 h ageing at 190 °C.
    effect: Table 3 of the paper lists corrosion potential and corrosion current density for the as-cast, solution-treated and three ageing conditions. In this laboratory test the current density rises and the corrosion potential falls with each step of ageing. The paper reports no corrosion rate or weight loss.
    rating: unknown
    conditions:
      basis: polarization data (Ecorr and Icorr) in Table 3 of the paper
      test: laboratory test in 3.5 wt.% NaCl, test standard not stated in the text read
      alloy: laboratory casting, Si 7.00 and Mg 0.45 wt.% (Table 1), not the datasheet grade
    source: jang-2025-corrosion
    where: Table 3, rows As-cast and SA9
risks:
  hazards:
    - text: PubChem's aluminum record lists GHS H228 (flammable solid) and H261 (in contact with water releases flammable gas), both with the signal word Danger. The record does not say which physical form these entries refer to, so this profile does not apply them to a cast part.
      ghs:
        - H228
        - H261
      source: pubchem-al
      where: GHS Classification section, CID 5359268
  failure_risks:
    - mode: Low elongation in T6 castings under tensile overload
      trigger: Tensile load on a T6 casting, in permanent-mould or sand-cast form
      consequence: Elongation is 5 to 12 % in T6 permanent-mould castings and 3 to 10 % in T6 sand castings. The datasheet gives no failure threshold.
      severity: moderate
      source: xometry-a356
      where: Section 3, Mechanical properties table, row Elongation
  handling:
    - text: PubChem's flammable-solid entry carries precaution codes P210, P231+P232, P240, P241, P280, P370+P378, P402+P404 and P501. Their wording is on the PubChem page and was not read in this run.
      source: pubchem-al
      where: GHS Classification section, precautionary statements for H228
uses:
  - application: structures
    device: Automotive wheels, engine blocks and transmission housings
    example: Xometry lists wheels, engine blocks, transmission housings, oil pans and rear axle housings as typical automotive applications for A356.
    source: xometry-a356
    where: Section 5, Typical applications
  - application: structures
    device: Aerospace structural castings, brackets and housings (non-load-bearing)
    example: Xometry lists aerospace structural castings, brackets and housings, and marks them as non-load-bearing components.
    source: xometry-a356
    where: Section 5, Typical applications
  - application: structures
    device: Space-use material for Japan's H-IIA and H-IIB rockets (the release does not name the part)
    example: NIMS and JAXA issued Data Sheet No. 12 on fracture toughness and high-cycle fatigue of cast A356-T6, for the reliability of the H-IIA and H-IIB rockets.
    source: nims-2009
    where: Press release of 2009.06.04, paragraph 2
  - application: structures
    device: Space-use material for Japan's H-IIA and H-IIB rockets (fatigue crack propagation)
    example: NIMS and JAXA issued Data Sheet No. 17 on fatigue crack propagation of cast A356-T6 castings.
    source: nims-2011
    where: Press release of 2011.03.31, abstract
supply:
  - subject: Aluminium (primary metal, the base of the alloy)
    producers:
      - country: China
        share_percent: 60.8
        year: 2025
      - country: India
        share_percent: 5.7
        year: 2025
      - country: Russia
        share_percent: 5.3
        year: 2025
      - country: Canada
        share_percent: 4.5
        year: 2025
      - country: United Arab Emirates
        share_percent: 3.6
        year: 2025
    critical_lists: []
    recycling: 'USGS: in 2025 about 3.6 million tons of aluminum were recovered from purchased scrap in the United States, of which about 56% came from new scrap.'
    substitutes:
      - 'USGS: composites, magnesium, steel and titanium can substitute for aluminum in ground transportation uses, and copper can replace aluminum in electrical and heat-exchange applications.'
    source: usgs-mcs2026-aluminum
    where: World Smelter Production and Capacity table, 2025e (world total 74,000 thousand t; shares calculated by Space Mushroom as production divided by the world total, the 'Other countries' row not listed); Recycling; Substitutes
documents:
  - title: Xometry A356 aluminum alloy datasheet (PDF)
    type: datasheet
    url: https://xometry.asia/wp-content/uploads/2025/07/1774070994-A356-Datasheet.pdf
    year: 2025
  - title: 'Total Materia: UNS A13560 Aluminium Alloys (physical properties and equivalents)'
    type: database
    url: https://www.totalmateria.com/en-us/material/3001883
    year: 2026
  - title: 'SAE AMS4218A: Aluminum alloy castings, premium grade 7Si - 0.3Mg (A356)'
    type: standard
    url: https://saemobilus.sae.org/content/ams4218a
    year: 2015
  - title: 'USGS Mineral Commodity Summaries 2026: Aluminum'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf
    year: 2026
  - title: 'PubChem compound record: Aluminum (CID 5359268), GHS classification'
    type: database
    url: https://pubchem.ncbi.nlm.nih.gov/compound/5359268
    year: 2026
  - title: 'NIMS press release: Data sheets on strength of space use materials (2009.06.04)'
    type: report
    url: https://archive.nims.go.jp/eng/news/press/2009/06/p200906040.html
    year: 2009
  - title: 'NIMS and JAXA press release: Data sheets No. 17 and No. 18 on space use materials (2011.03.31)'
    type: report
    url: https://archive.nims.go.jp/eng/news/press/2011/03/p201103311.html
    year: 2011
  - title: Effect of Heat Treatment on Corrosion Resistance of A356 Casting Alloy (Materials 18(5):1056, 2025)
    type: paper
    url: https://pmc.ncbi.nlm.nih.gov/articles/PMC11901162/
    year: 2025
gaps:
  - Jang et al. 2025 (Materials, 18(5):1056) is the only corrosion test read. It uses a laboratory casting with Si 7.00 and Mg 0.45 wt.%, not the datasheet grade, and reports no corrosion rate or weight loss. The Manchester rheocast A356 corrosion paper was not readable (access denied), so the datasheet corrosion rows stay qualitative.
  - Coefficient of thermal expansion (21.5 × 10⁻⁶ /°C in the Xometry datasheet) and thermal diffusivity (60 × 10⁻⁶ m²/s) are printed with exponents, so they are left out.
  - Crustal abundance of aluminium was not found in the USGS PP 1802-A text we could read, so no abundance is recorded.
  - The USGS 2025 critical minerals page returned an access block (403), so aluminium's status on the critical lists is not recorded and critical_lists is empty.
  - No flight or space test values for A356 were found. The NIMS and JAXA data sheets exist, but their press releases print no numeric values.
  - The Xometry cross-reference lists EN AC-42000 and other equivalents. The datasheet calls them equivalents, not the same grade, so they are not listed as designations.
  - No safety data sheet for the A356 casting alloy was read. PubChem's aluminum hazard entries do not say which physical form they cover.
  - Ageing and overageing data (for example Daswa et al., Solid State Phenomena 2019) were not opened. Jang et al. 2025 gives Vickers hardness after 3, 6 and 9 h at 190 °C on a laboratory casting, recorded above. No ageing strength or elongation was found.
  - Guaranteed minimum mechanical values (AMS4218 or ASTM B26, B108) were not read; the values here are datasheet ranges, which the datasheet does not describe as minimums.
  - 'Custom benchmark names used: electrical_conductivity, brinell_hardness, shear_strength, fracture_toughness, charpy_impact_energy, vickers_hardness, corrosion_current_density.'
  - Jang et al. 2025 reports no tensile, yield or elongation values for its laboratory casting, so no mechanical row is taken from it.
  - The Jang et al. summary quotes "the hardness of A356-SA9 was 92.38 HV", while its Section 3.2 table prints 92.8 HV. The table value is recorded and the summary figure is left out.
sources:
  xometry-a356:
    title: A356 Aluminum Alloy datasheet (Xometry)
    id: file 1774070994-A356-Datasheet.pdf
    url: https://xometry.asia/wp-content/uploads/2025/07/1774070994-A356-Datasheet.pdf
    year: 2025
    kind: datasheet
    license: Xometry datasheet, cited and not reproduced
  totalmat-a13560:
    title: UNS A13560 Aluminium Alloys (Total Materia)
    id: UNS A13560, Metals and alloys in the unified numbering system (UNS), 2025
    url: https://www.totalmateria.com/en-us/material/3001883
    year: 2026
    kind: database
    license: Total Materia, cited and not reproduced
  ams4218:
    title: 'AMS4218A: Aluminum alloy castings, premium grade 7Si - 0.3Mg (A356) (SAE material specification)'
    id: SAE AMS4218A, DOI 10.4271/AMS4218A
    url: https://saemobilus.sae.org/content/ams4218a
    year: 2015
    kind: standard
    license: SAE International, cited and not reproduced
  usgs-mcs2026-aluminum:
    title: 'Mineral Commodity Summaries 2026: Aluminum'
    id: USGS MCS 2026, February 2026
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf
    year: 2026
    kind: report
    license: public domain (USGS)
  pubchem-al:
    title: 'PubChem compound record: Aluminum (CID 5359268)'
    id: CID 5359268
    url: https://pubchem.ncbi.nlm.nih.gov/compound/5359268
    year: 2026
    kind: database
    license: public domain (NCBI)
  nims-2009:
    title: NIMS issues new data sheets on strength of space use materials (press release, 2009.06.04)
    id: NIMS Data Sheet No. 12
    url: https://archive.nims.go.jp/eng/news/press/2009/06/p200906040.html
    year: 2009
    kind: web
    license: NIMS press release, cited and not reproduced
  nims-2011:
    title: NIMS and JAXA issue data sheets on mechanical properties of space use materials No. 17 and No. 18 (press release, 2011.03.31)
    id: NIMS Data Sheet No. 17
    url: https://archive.nims.go.jp/eng/news/press/2011/03/p201103311.html
    year: 2011
    kind: web
    license: NIMS press release, cited and not reproduced
  jang-2025-corrosion:
    title: Effect of Heat Treatment on Corrosion Resistance of A356 Casting Alloy (Materials, 2025)
    id: DOI 10.3390/ma18051056, PMC11901162
    url: https://pmc.ncbi.nlm.nih.gov/articles/PMC11901162/
    year: 2025
    kind: paper
    license: open access (MDPI, Materials), cited and not reproduced
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 24
  unreachable: 3
  caveats: 2
  note: Written by an AI assistant on 2026-11-01 from the Xometry datasheet, Total Materia UNS A13560 page, SAE AMS4218A page, USGS MCS 2026 aluminum summary, PubChem, NIMS press releases and the Jang et al. 2025 paper. Corrosion data come from that one laboratory paper. Ageing strength and critical-list data were not found in readable sources.
story:
  recipe:
    line: A356.0 is an aluminium alloy, not a compound, so its make-up is a range of mass percentages rather than a formula. Silicon and magnesium are the alloying elements, and aluminium is the balance.
    parts:
      - name: Aluminium
        symbol: Al
        share_note: balance
        role: Base metal and the balance of the alloy.
      - name: Silicon
        symbol: Si
        share_percent: 6.5
        share_high: 7.5
        role: Main alloying element. The datasheet says it improves fluidity and castability.
      - name: Magnesium
        symbol: Mg
        share_percent: 0.25
        share_high: 0.45
        role: Reinforcing element. The datasheet says it allows strengthening by heat treatment.
      - name: Iron
        symbol: Fe
        share_note: 0.20 maximum
        role: Impurity, held under a stringent limit.
      - name: Copper
        symbol: Cu
        share_note: 0.20 maximum
        role: Impurity. Excess can reduce corrosion resistance, per the datasheet.
      - name: Zinc
        symbol: Zn
        share_note: 0.10 maximum
        role: Impurity.
      - name: Manganese
        symbol: Mn
        share_note: 0.10 maximum
        role: Impurity.
      - name: Titanium
        symbol: Ti
        share_note: 0.20 maximum
        role: Grain refiner.
  risk_groups:
    - title: For people
      level: 0
      verdict: No hazard class for the cast alloy in the sources read
      lead: The datasheet gives no hazard statement for the casting alloy. PubChem's aluminum record lists flammable and water-reactive classes for an unnamed physical form.
      points:
        - label: The cast alloy
          line: No safety data sheet for the A356 casting was read in this run, so no hazard class is given for a cast part.
        - label: Aluminum record
          line: PubChem lists H228 (flammable solid) and H261 (in contact with water releases flammable gas), but does not say which physical form they refer to.
    - title: Handling and strength
      lead: The points below come from the datasheet and from PubChem's precautionary codes.
      points:
        - label: Precaution codes
          line: PubChem's flammable-solid entry carries the codes P210, P231+P232, P240, P241, P280, P370+P378, P402+P404 and P501. Their wording was not read in this run.
        - label: Elongation
          line: Elongation is 5 to 12 % in T6 permanent-mould castings and 3 to 10 % in T6 sand castings, per the Xometry datasheet.
  why: A356.0 (UNS A13560) is an aluminium-silicon-magnesium casting alloy. Silicon from 6.5 to 7.5 % improves how the molten metal flows into thin, complex moulds. Magnesium from 0.25 to 0.45 % allows the alloy to be strengthened by T6 heat treatment, per the Xometry datasheet. The datasheet gives a density of 2.68 g/cm3, and the alloy is used for automotive wheels and for aerospace brackets and housings. NIMS and JAXA have also issued strength data sheets for cast A356-T6 used in Japan's H-IIA and H-IIB rockets.
  uses:
    - where: Automotive
      line: Xometry lists wheels, engine blocks and transmission housings among the typical uses of A356.
    - where: Aerospace
      line: Xometry lists structural castings, brackets and housings for aerospace. The datasheet marks them as non-load-bearing components.
    - where: Space hardware
      line: NIMS and JAXA issued strength data sheets for cast A356-T6 as a space-use material for Japan's H-IIA and H-IIB rockets. The data sheets cover fracture toughness, high-cycle fatigue and fatigue crack propagation. The press releases do not name the parts.
  can_do:
    - label: Tensile strength
      benchmark: ultimate_tensile_strength
      line: A T6 permanent-mould casting has a tensile strength of 276 to 345 MPa. A T6 sand casting has 234 to 310 MPa. Both are ranges from one datasheet, which does not say whether they are minimums.
    - label: Density
      benchmark: density
      line: The density is 2.68 g/cm3 in the Xometry datasheet. Total Materia gives 2.6 to 2.9 kg/dm3 for the same UNS number, a wider range.
    - label: Stiffness
      benchmark: elastic_modulus
      line: The elastic modulus is 72.4 GPa in the Xometry datasheet and 69 to 79 GPa on Total Materia. The two sources differ.
    - label: Heat conduction
      benchmark: thermal_conductivity
      line: Thermal conductivity is 149 to 155 W/(m·K) in the T6 temper, per the datasheet.
    - label: Hardness
      benchmark: brinell_hardness
      line: A T6 permanent-mould casting has a Brinell hardness of 80 to 100 HB.
    - label: Melting range
      benchmark: melting_point
      line: The melting range, from solidus to liquidus, is 557 to 613 °C.
  compare: Among the aluminium casting alloys in this collection, A356 is the silicon-magnesium grade with a silicon range of 6.5 to 7.5 %. The datasheet does not compare A356 with other alloys, so this profile makes no ranking claim. The three rows below set its density, tensile strength and thermal conductivity beside the other profiles in the collection.
  compare_rows:
    - label: Density
      benchmark: density
    - label: Tensile strength (T6 permanent mould)
      benchmark: ultimate_tensile_strength
    - label: Thermal conductivity (T6)
      benchmark: thermal_conductivity
  handling:
    - Check the composition and temper against the casting specification (AMS4218 for the premium grade, or ASTM B26 and B108 in the cross-reference), not against a grade summary.
    - PubChem's flammable-solid and water-reactive entries do not say which physical form they cover. Keep fine powder and swarf dry and away from heat (codes P210 and P280 are printed in the PubChem entry).
  good_for:
    - Thin-walled, complex castings that need good fluidity, per the Xometry datasheet.
    - Heat-treated castings that need a T6 permanent-mould tensile strength of 276 to 345 MPa.
  watch_out:
    - Elongation is only 5 to 12 % in T6 permanent-mould castings and 3 to 10 % in T6 sand castings.
    - Excess impurities, including copper, may reduce corrosion resistance, according to the datasheet. No corrosion rate is given.
    - 'The two sources disagree on elastic modulus: 72.4 GPa in the Xometry datasheet and 69 to 79 GPa on Total Materia.'
  verdict: A356.0 is a heat-treatable casting alloy with datasheet strength ranges. The sources read here give one laboratory corrosion study on a casting with a different composition, no flight data and no guaranteed minimum values.