spore: profile
id: zinc-aluminium-za-12-za-27
spore_version: 0.2
family: zinc-alloys
name: Zinc-aluminium ZA-12 and ZA-27 foundry alloys
abbreviation: ZA-12, ZA-27
role: gravity and die casting alloy for bearings and wear parts
category: metals
type: heavy-metals
summary: |
  ZA-12 and ZA-27 are zinc-base foundry alloys with aluminium as the main alloying element. Eazall prints an ingot aluminium content of 10.8 to 11.5 % for ZA-12 and 25.5 to 28.0 % for ZA-27 (ASTM B240 composition). Eazall's typical die cast tensile strength is 400 MPa for ZA-12 and 421 MPa for ZA-27, with yield strengths of 317 MPa and 379 MPa. ZA-27 is the lighter alloy at 5.0 g/cc against 6.0 g/cc for ZA-12 (Eazall), but ZA-12 stretches more, at 4 to 7 % elongation against 1 to 3 %. Sources disagree on the ZA-12 density (5.6 g/cm3 per Firstmold) and on the ZA-27 tensile strength, and both are recorded side by side.
best_for: Gravity-cast or die-cast bearings, bushings and wear parts that need more strength than zinc die-casting alloys (Total Materia and Eazall)
weakest_at: Molten metal reacts violently with water, and the melt gives off zinc oxide fume (Bridesburg SDS); ZA-27 has the least castability of the pair (Firstmold)
identity:
  formula: 'Zinc-base alloys, weight %. ZA-12 ingot (ASTM B240, Eazall): Al 10.8 to 11.5, Cu 0.5 to 1.2, Mg 0.02 to 0.03, Fe 0.05 max, Pb 0.005 max, Cd 0.005 max, Sn 0.002 max, Zn balance; Eazall lists no nickel. ZA-12 die casting (ASTM B86, Eazall): Cu 0.8 to 1.2, Mg 0.01 to 0.03, Fe 0.075 max, Pb 0.006 max, Cd 0.006 max, Sn 0.003 max, Zn balance; the die casting aluminium figure is printed as "10-5-11.5", a probable typo, and is not recorded. ZA-27 ingot (ASTM B240, Eazall): Al 25.5 to 28.0, Cu 2.0 to 2.5, Mg 0.012 to 0.02, Fe 0.07 max, Pb 0.005 max, Cd 0.005 max, Sn 0.002 max, Zn balance. ZA-27 die casting (ASTM B86, Eazall): Al 25.0 to 28.0, Cu 2.0 to 2.5, Mg 0.01 to 0.02, Fe 0.075 max, Pb 0.006 max, Cd 0.006 max, Sn 0.003 max, Zn balance.'
  source: eazall-za12
  where: ZA-12 values from the Chemical Analysis table of the Eazall ZA-12 page; ZA-27 values from the Chemical Analysis table of the Eazall ZA-27 page (source eazall-za27)
  designations:
    - system: Trade name
      code: ZA-12
      source: eazall-za12
      where: Page heading and alloy name in the Eazall ZA-12 page
    - system: Trade name
      code: ZA-27
      source: eazall-za27
      where: Page heading and alloy name in the Eazall ZA-27 page
    - system: ASTM
      code: B240
      note: ZA-12 ingot composition
      source: eazall-za12
      where: Chemical Analysis table, Ingot (ASTM B240) column
    - system: ASTM
      code: B86
      note: ZA-12 die casting composition
      source: eazall-za12
      where: Chemical Analysis table, Die Cast (ASTM B86) column
    - system: ISO
      code: ZP27
      note: ZA-27
      source: icast-za27
      where: Cross Reference Table, ISO row
tags:
  applications:
    - mechanisms
    - structures
properties:
  - benchmark: ultimate_tensile_strength
    value: 400
    unit: MPa
    scope: material
    conditions:
      alloy: ZA-12
      form: typical die casting
      unit_in_source: 58 (400) ksi (MPa)
      basis: typical value, not a minimum
    method: Typical die cast mechanical properties table, metric value in parentheses as printed
    status: ground
    source: eazall-za12
    where: Typical Die Cast Mechanical Properties table, UTS row
  - benchmark: yield_strength
    value: 317
    unit: MPa
    scope: material
    conditions:
      alloy: ZA-12
      form: typical die casting
      unit_in_source: 46 (317) ksi (MPa)
      basis: typical value, not a minimum
    method: Typical die cast mechanical properties table, metric value in parentheses as printed
    status: ground
    source: eazall-za12
    where: Typical Die Cast Mechanical Properties table, Yield Strength row
  - benchmark: elongation
    value: 4
    value_high: 7
    bound: range
    unit: '%'
    scope: material
    conditions:
      alloy: ZA-12
      form: typical die casting
    method: Typical die cast mechanical properties table, range as printed
    status: ground
    source: eazall-za12
    where: Typical Die Cast Mechanical Properties table, Elongation row
  - benchmark: brinell_hardness
    value: 95
    value_high: 115
    bound: range
    unit: Brinell
    scope: material
    conditions:
      alloy: ZA-12
      form: typical die casting
      unit_in_source: Brinell
    method: Typical die cast mechanical properties table, range as printed (benchmark name not in property-canon.yaml)
    status: ground
    source: eazall-za12
    where: Typical Die Cast Mechanical Properties table, Hardness row
  - benchmark: density
    value: 6
    unit: g/cc
    scope: material
    conditions:
      alloy: ZA-12
      form: typical die casting
      unit_in_source: 0.218 (6.0) lb/in^3 (g/cc)
    method: Typical die cast physical properties table, metric value in parentheses as printed
    status: ground
    source: eazall-za12
    where: Typical Die Cast Physical Properties table, Density row
  - benchmark: density
    value: 5.6
    unit: g/cm3
    scope: material
    conditions:
      alloy: ZA-12
      form: not stated on the page
    method: Comparison table of ZA alloy data on the Firstmold page, ZA-12 column; conflicts with the Eazall value of 6.0 g/cc
    status: ground
    source: firstmold-zinc
    where: ZA alloy data table, density row, ZA-12 column
  - benchmark: melting_point
    value: 377
    value_high: 432
    bound: range
    unit: °C
    scope: material
    conditions:
      alloy: ZA-12
      form: typical die casting
      unit_in_source: 710-810 (377-432) deg F (deg C)
    method: Typical die cast physical properties table, melt range in deg C as printed in parentheses
    status: ground
    source: eazall-za12
    where: Typical Die Cast Physical Properties table, Melt Range row
  - benchmark: electrical_conductivity
    value: 28.3
    unit: '%IACS'
    scope: material
    conditions:
      alloy: ZA-12
      form: typical die casting
    method: Typical die cast physical properties table as printed (benchmark name not in property-canon.yaml)
    status: ground
    source: eazall-za12
    where: Typical Die Cast Physical Properties table, Electrical Conduct row
  - benchmark: specific_heat
    value: 0.107
    unit: BTU/lb/deg F
    scope: material
    conditions:
      alloy: ZA-12
      form: typical die casting
    method: Typical die cast physical properties table, value and unit as printed
    status: ground
    source: eazall-za12
    where: Typical Die Cast Physical Properties table, Specific Heat row
  - benchmark: die_shrinkage
    value: 0.0075
    unit: in/in
    scope: material
    conditions:
      alloy: ZA-12
      form: typical die casting
    method: Typical die cast physical properties table as printed (benchmark name not in property-canon.yaml)
    status: ground
    source: eazall-za12
    where: Typical Die Cast Physical Properties table, Die Shrinkage row
  - benchmark: casting_temperature
    value: 480
    value_high: 540
    bound: range
    unit: °C
    scope: material
    conditions:
      alloy: ZA-12
      process: melt temperature for casting, not a melting point
      unit_in_source: 480-540°C
    method: Die casting section of the Total Materia article, stated as about 50 degC lower than ZA-27; benchmark name not in property-canon.yaml
    status: ground
    source: totalmateria-za
    where: Die Casting the ZA Alloys section, ZA-12 paragraph
  - benchmark: ultimate_tensile_strength
    value: 421
    unit: MPa
    scope: material
    conditions:
      alloy: ZA-27
      form: typical die casting
      unit_in_source: 61 ksi (421 MPa)
      basis: typical value, not a minimum
    method: Typical die cast mechanical properties table, metric value in parentheses as printed
    status: ground
    source: eazall-za27
    where: Typical Die Cast Mechanical Properties table, UTS row
  - benchmark: yield_strength
    value: 379
    unit: MPa
    scope: material
    conditions:
      alloy: ZA-27
      form: typical die casting
      unit_in_source: 55 ksi (379 MPa)
      basis: typical value, not a minimum
    method: Typical die cast mechanical properties table, metric value in parentheses as printed
    status: ground
    source: eazall-za27
    where: Typical Die Cast Mechanical Properties table, Yield Strength row
  - benchmark: elongation
    value: 1
    value_high: 3
    bound: range
    unit: '%'
    scope: material
    conditions:
      alloy: ZA-27
      form: typical die casting
    method: Typical die cast mechanical properties table, range as printed
    status: ground
    source: eazall-za27
    where: Typical Die Cast Mechanical Properties table, Elongation row
  - benchmark: brinell_hardness
    value: 105
    value_high: 125
    bound: range
    unit: Brinell
    scope: material
    conditions:
      alloy: ZA-27
      form: typical die casting
      unit_in_source: Brinell
    method: Typical die cast mechanical properties table, range as printed (benchmark name not in property-canon.yaml)
    status: ground
    source: eazall-za27
    where: Typical Die Cast Mechanical Properties table, Hardness row
  - benchmark: density
    value: 5
    unit: g/cc
    scope: material
    conditions:
      alloy: ZA-27
      form: typical die casting
      unit_in_source: 0.181 (5.0 g/cc) lb/in^3
    method: Typical die cast physical properties table, metric value in parentheses as printed
    status: ground
    source: eazall-za27
    where: Typical Die Cast Physical Properties table, Density row
  - benchmark: melting_point
    value: 375
    value_high: 484
    bound: range
    unit: °C
    scope: material
    conditions:
      alloy: ZA-27
      form: typical die casting
      unit_in_source: 708-903 deg F (375-484 deg C)
    method: Typical die cast physical properties table, melt range in deg C as printed in parentheses
    status: ground
    source: eazall-za27
    where: Typical Die Cast Physical Properties table, Melt Range row
  - benchmark: electrical_conductivity
    value: 29.7
    unit: '%IACS'
    scope: material
    conditions:
      alloy: ZA-27
      form: typical die casting
    method: Typical die cast physical properties table as printed (benchmark name not in property-canon.yaml)
    status: ground
    source: eazall-za27
    where: Typical Die Cast Physical Properties table, Electrical Conductivity row
  - benchmark: specific_heat
    value: 0.125
    unit: BTU/lb/deg F
    scope: material
    conditions:
      alloy: ZA-27
      form: typical die casting
    method: Typical die cast physical properties table, value and unit as printed
    status: ground
    source: eazall-za27
    where: Typical Die Cast Physical Properties table, Specific Heat row
  - benchmark: die_shrinkage
    value: 0.008
    unit: in/in
    scope: material
    conditions:
      alloy: ZA-27
      form: typical die casting
    method: Typical die cast physical properties table as printed (benchmark name not in property-canon.yaml)
    status: ground
    source: eazall-za27
    where: Typical Die Cast Physical Properties table, Die Shrinkage row
  - benchmark: casting_temperature
    value: 540
    value_high: 590
    bound: range
    unit: °C
    scope: material
    conditions:
      alloy: ZA-27
      process: melt held for die casting, not a melting point
      unit_in_source: 540-590°C
    method: Die casting section of the Total Materia article, melt temperature as printed; benchmark name not in property-canon.yaml
    status: ground
    source: totalmateria-za
    where: Die Casting the ZA Alloys section, ZA-27 paragraph
  - benchmark: ultimate_tensile_strength
    value: 426
    unit: MPa
    scope: material
    conditions:
      alloy: ZA-27
      form: not stated on the page
      note_on_form: stated only as the upper end of a range from ZA-8 to ZA-27
    method: Introduction of the Total Materia article, range ending at 426 MPa for ZA-27; conflicts with the Eazall typical value of 421 MPa
    status: ground
    source: totalmateria-za
    where: Introduction, tensile strength sentence
  - benchmark: ultimate_tensile_strength
    value: 310
    value_high: 441
    bound: range
    unit: MPa
    scope: material
    conditions:
      alloy: ZA-27
      form: casting, as-cast or aged
      unit_in_source: 310 - 441 Mpa
    method: Mechanical properties table of the ICAST ZA-27 datasheet, range as printed
    status: ground
    source: icast-za27
    where: Mechanical properties table, Tensile Strength row (datasheet headed UNS Z35841)
  - benchmark: yield_strength
    value: 257
    value_high: 376
    bound: range
    unit: MPa
    scope: material
    conditions:
      alloy: ZA-27
      form: casting, as-cast or aged
      unit_in_source: 257 - 376 Mpa
    method: Mechanical properties table of the ICAST ZA-27 datasheet, range as printed
    status: ground
    source: icast-za27
    where: Mechanical properties table, Yield Strength row (datasheet headed UNS Z35841)
  - benchmark: elongation
    value: 1
    value_high: 11
    bound: range
    unit: '%'
    scope: material
    conditions:
      alloy: ZA-27
      form: casting, as-cast or aged
    method: Mechanical properties table of the ICAST ZA-27 datasheet, range as printed; wider than the Eazall range
    status: ground
    source: icast-za27
    where: Mechanical properties table, Elongation row (datasheet headed UNS Z35841)
  - benchmark: brinell_hardness
    value: 94
    value_high: 119
    bound: range
    unit: HB
    scope: material
    conditions:
      alloy: ZA-27
      form: casting, as-cast or aged
    method: Mechanical properties table of the ICAST ZA-27 datasheet, range as printed (benchmark name not in property-canon.yaml)
    status: ground
    source: icast-za27
    where: Mechanical properties table, Hardness in HB row (datasheet headed UNS Z35841)
checked_values: 26
corrosion:
  - environment: Aqueous exposure (water and aqueous solutions)
    headline: ZA alloys resist corrosion less than aluminium but better than Zamac, and the pH of the water should stay close to neutral.
    effect: Total Materia says the corrosion resistance of ZA alloys tends to fall between that of the Zamac alloys and aluminium, and that for aqueous exposure the pH should be kept close to neutral. No test rate or time-to-failure for bare ZA-12 or ZA-27 was found in a source we read.
    rating: moderate
    conditions:
      basis: qualitative statement in the technical concerns section, not a measured rate
      alloys: ZA alloys in general, including ZA-12 and ZA-27
    source: totalmateria-za
    where: Technical Concerns section, corrosion paragraphs
  - environment: Finished surfaces in salt spray
    headline: Finishes protect the alloy; the salt-spray result quoted is for zinc anodizing, not for bare ZA alloy.
    effect: Total Materia lists chromating, electroplating, painting and zinc anodizing as finishing options, and says zinc anodizing has withstood several thousand hours of neutral salt spray testing. The page prints the test standard as ASTM 8117, which is probably a typo for ASTM B117, and gives no bare-alloy salt-spray result.
    rating: unknown
    conditions:
      basis: finish-specific result as printed; no bare-alloy test
      test: neutral salt spray, standard printed as ASTM 8117
    source: totalmateria-za
    where: Technical Concerns section, finishing options paragraph
risks:
  hazards:
    - text: The Bridesburg SDS for ZA-8, ZA-12 and ZA-27 says the product is not hazardous under the US Hazard Communication Standard, with no ingredients qualifying, but it lists burn, dust and fume hazards.
      ghs: []
      source: bridesburg-za-sds
      where: Hazard identification, Other Hazards list; regulatory information block (Hazardous Under Hazard Communication Standard line)
    - text: Molten alloy burns the skin and eyes on contact, according to the Bridesburg SDS.
      ghs: []
      source: bridesburg-za-sds
      where: Hazard identification, skin and eye contact in molten state
    - text: Burning or melting the alloy forms metallic zinc oxide fume, which is the special exposure hazard the Bridesburg SDS names.
      ghs: []
      source: bridesburg-za-sds
      where: Fire-fighting measures, special exposure hazards; Other Hazards list (fume inhalation on melting)
  failure_risks:
    - mode: Molten alloy reacting with water or moisture
      trigger: Water, damp material or moisture entering a molten bath
      consequence: Violent to explosive reaction, per the Bridesburg SDS (in molten state, with water or moisture)
      severity: high
      source: bridesburg-za-sds
      where: Reactivity and stability, in molten state
    - mode: Zinc oxide fume from an overheated melt
      trigger: Overheating a molten bath to or near the boiling point
      consequence: Metal fume fever, a transient influenza-like illness, on inhalation in sufficient quantity (Teck zinc metal SDS; zinc metal, not the ZA alloy)
      severity: moderate
      source: teck-zinc-sds
      where: Fire-fighting measures, overheated molten bath paragraph
  side_effects:
    - text: Zinc compounds can be toxic, particularly in aquatic environments, so releases to water and soil should be prevented (Teck zinc metal SDS; zinc metal, not the ZA alloy).
      affects: Waterways, drains and soil near the foundry
      source: teck-zinc-sds
      where: Ecological information
  handling:
    - text: Add only dry material to the metal bath (Bridesburg SDS, handling section).
      source: bridesburg-za-sds
      where: Handling and storage, list item on dry material
    - text: Dry ingots thoroughly before adding them to a molten bath, because damp zinc can react violently with the melt (Teck zinc metal SDS).
      source: teck-zinc-sds
      where: Handling and storage, ingots paragraph
    - text: Wear heat-resistant gloves and suitable clothing where molten metal is involved, and respiratory protection against dust and fume (Teck zinc metal SDS).
      source: teck-zinc-sds
      where: Personal protection, hand and body protection
  mitigations:
    - text: For a metal fire, use dry chemical, dry sand or special powder (Class D) extinguishing media, and do not use water, carbon dioxide or foam on molten metal (Bridesburg SDS).
      source: bridesburg-za-sds
      where: Fire-fighting measures, suitable and unsuitable extinguishing media
    - text: In a metal bath fire, add metal blocks to smother it, and dilute toxic gases with a water spray (Bridesburg SDS).
      source: bridesburg-za-sds
      where: Fire-fighting measures, instructions
uses:
  - application: mechanisms
    device: Bearings and bushings
    example: Total Materia describes gravity cast ZA-12 and ZA-27 as direct substitutes for bronze industrial bearings.
    source: totalmateria-za
    where: Introduction
  - application: mechanisms
    device: Wear and bearing parts
    example: Eazall says ZA-27 is the lightest alloy available and has excellent bearing and wear performance.
    source: eazall-za27
    where: Use, application and processing text
  - application: structures
    device: Weight-bearing castings
    example: Firstmold recommends ZA-12 and ZA-27 where weight-bearing capacity and dimensional stability under load are of prime importance.
    source: firstmold-zinc
    where: Uses paragraph for ZA-12 and ZA-27
supply:
  - subject: Zinc
    producers:
      - country: China
        share_percent: 31.5
        year: 2025
      - country: Peru
        share_percent: 11.5
        year: 2025
      - country: Australia
        share_percent: 8.5
        year: 2025
      - country: India
        share_percent: 6.7
        year: 2025
      - country: Mexico
        share_percent: 6
        year: 2025
    critical_lists: []
    recycling: 'USGS: refined zinc produced in the United States was recovered from secondary materials at both primary and secondary smelters, including galvanizing residues and crude zinc oxide from electric arc furnace dust.'
    substitutes:
      - 'USGS: aluminum- and magnesium-base alloys are major substitutes for zinc-base diecasting alloys.'
    source: usgs-zinc-2026
    where: World Mine Production and Reserves table, 2025e column (shares calculated here against the rounded world total of 13,000 thousand t); Recycling; Substitutes. No critical-list statement was found in this chapter.
  - subject: Aluminium
    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: aluminum recovered from purchased scrap in the United States was about 3.6 million tons in 2025, about 56% of it from new scrap.'
    substitutes: []
    source: usgs-aluminum-2026
    where: World Smelter Production table, 2025e column (shares calculated here against the rounded world total of 74,000 thousand t); Recycling. No critical-list statement was found in this chapter.
media: []
documents:
  - title: Eazall ZA-12 alloy data page
    type: datasheet
    url: https://www.eazall.com/za12
    year: 2026
  - title: Eazall ZA-27 alloy data page
    type: datasheet
    url: https://www.eazall.com/za27
    year: 2026
  - title: ICAST Alloys datasheet, UNS Z35841 (ZA-27 table)
    type: datasheet
    url: https://icastllp.com/material_db_pdf/UNS%20Z35841.pdf
    year: 2026
  - title: Bridesburg Foundry safety data sheet, ZA Alloys (ZA-8, ZA-12, ZA-27)
    type: sds
    url: https://bridesburg.com/wp-content/uploads/2025/03/BF-ZA-Alum-SDS-1.pdf
    year: 2025
  - title: Teck zinc metal safety data sheet
    type: sds
    url: https://www.teck.com/media/Zinc_Metal_SDS.pdf
    year: 2026
  - title: 'USGS Mineral Commodity Summaries 2026: zinc'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-zinc.pdf
    year: 2026
  - title: 'USGS Mineral Commodity Summaries 2026: aluminum'
    type: report
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf
    year: 2026
gaps:
  - No UNS number is recorded. UNS Z35841 is printed on an ICAST datasheet whose title names ZA-12 while its table is headed ZA-27, so the page is internally inconsistent; no other source read in this run printed a UNS code for ZA-12 or ZA-27.
  - No EN material number or EN name was found for ZA-12 or ZA-27 in any source read in this run.
  - 'Modulus of elasticity not recorded: Eazall prints 12.0 psi x 10^6 (ZA-12) and 11.3 psi x 10^6 (ZA-27) in an exponent format, which is not recorded; Total Materia and ICAST print no modulus value.'
  - No thermal conductivity value was found for ZA-12 or ZA-27 (Eazall says it does not list one; Total Materia gives none).
  - No numeric melting or liquidus or solidus temperatures beyond the Eazall melt ranges; Total Materia gives casting temperatures only.
  - ZA-12 die casting aluminium is printed as 10-5-11.5 on the Eazall page, a probable typo for 10.5 to 11.5; it is not recorded in the file.
  - 'Sources disagree: ZA-12 density is 6.0 g/cc per Eazall and 5.6 g/cm3 per Firstmold; ZA-27 tensile strength is 421 MPa per Eazall (typical die casting), 426 MPa per Total Materia (form not stated) and 310 to 441 MPa per ICAST (casting range). All are recorded.'
  - Firstmold labels ZA-12 "(12% Al)", while the Eazall ingot composition is 10.8 to 11.5 %; both are recorded and not reconciled.
  - Brinell hardness, electrical conductivity, die shrinkage and casting temperature use benchmark names that are not in property-canon.yaml, so they are snake_case or as printed and should be mapped by hand.
  - The Eazall ZA-12 and ZA-27 pages give typical die casting values only; no minimum-property standard (ASTM B86 text) was opened in this run.
  - No flight, space, vacuum, radiation or thermal-cycling data were found for ZA-12 or ZA-27.
  - No fatigue, creep or long-term dimensional data at a stated temperature were found in a source read in this run; Total Materia mentions creep and growth without numbers for ZA alloys.
  - No bare-alloy salt-spray or corrosion-rate test was found; the only salt-spray remark is for zinc anodizing, and its standard is printed as ASTM 8117.
  - Hazard data come from a supplier SDS for the ZA alloy family (Bridesburg) and a zinc metal SDS (Teck). No SDS with composition-specific hazard data for ZA-12 or ZA-27 alone was opened.
  - 'Critical-mineral list status for zinc and aluminium was not confirmed: the USGS chapters read here do not discuss critical-mineral lists, and the EU list was not checked.'
  - Supply shares are calculated from the USGS 2025e values, not printed by USGS; the zinc and aluminium world totals are rounded in the source.
sources:
  eazall-za12:
    title: 'Eazall: ZA-12 zinc aluminium alloy data'
    url: https://www.eazall.com/za12
    year: 2026
    kind: datasheet
  eazall-za27:
    title: 'Eazall: ZA-27 zinc aluminium alloy data'
    url: https://www.eazall.com/za27
    year: 2026
    kind: datasheet
  totalmateria-za:
    title: 'Total Materia: The Zinc-Aluminum Die Casting Alloys'
    url: https://www.totalmateria.com/pt/articles/the-zinc-aluminum-die-casting-alloys
    year: 2006
    kind: web
  firstmold-zinc:
    title: 'Firstmold: zinc casting tips (ZA alloy comparison)'
    url: https://firstmold.com/tips/zinc/
    year: 2026
    kind: web
  icast-za27:
    title: ICAST Alloys datasheet, Zinc-Aluminum ZA-27 casting (material code UNS Z35841)
    url: https://icastllp.com/material_db_pdf/UNS%20Z35841.pdf
    year: 2026
    kind: datasheet
  bridesburg-za-sds:
    title: Bridesburg Foundry safety data sheet, ZA Alloys (ZA-8, ZA-12, ZA-27)
    url: https://bridesburg.com/wp-content/uploads/2025/03/BF-ZA-Alum-SDS-1.pdf
    year: 2025
    kind: datasheet
  teck-zinc-sds:
    title: 'Teck: Zinc Metal safety data sheet'
    url: https://www.teck.com/media/Zinc_Metal_SDS.pdf
    year: 2026
    kind: datasheet
  usgs-zinc-2026:
    title: 'USGS Mineral Commodity Summaries 2026: Zinc'
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-zinc.pdf
    year: 2026
    kind: report
  usgs-aluminum-2026:
    title: 'USGS Mineral Commodity Summaries 2026: Aluminum'
    url: https://pubs.usgs.gov/periodicals/mcs2026/mcs2026-aluminum.pdf
    year: 2026
    kind: report
license: CC-BY-4.0
updated: '2026-11-01'
review:
  status: draft
  method: assistant
  checked_values: 26
  note: Written by an AI assistant on 2026-11-01 from pages read in that run. Values are typical or range figures as printed, and conflicts are recorded side by side.
story:
  recipe:
    line: ZA-12 and ZA-27 are zinc-base alloys. Zinc is the balance. Aluminium is the main alloying element, at 10.8 to 11.5 % in the ZA-12 ingot and 25.5 to 28.0 % in the ZA-27 ingot (Eazall, ASTM B240 composition). Copper and magnesium are added in small amounts. Eazall says ZA-12 can be gravity cast or die cast, and that ZA-27 must be cast in a cold chamber machine.
    parts:
      - name: Zinc
        symbol: Zn
        share: balance
        role: The base metal. It forms the matrix that carries the other alloying elements.
      - name: Aluminium
        symbol: Al
        share: 10.8 to 11.5 % (ZA-12 ingot); 25.5 to 28.0 % (ZA-27 ingot)
        role: Sets the alloy family. Firstmold labels ZA-12 "(12% Al)", which does not match the Eazall ingot range, and both figures are recorded.
      - name: Copper
        symbol: Cu
        share: 0.5 to 1.2 % (ZA-12 ingot); 2.0 to 2.5 % (ZA-27 ingot)
        role: Adds strength. Eazall prints a higher copper range for ZA-27 than for ZA-12.
      - name: Magnesium
        symbol: Mg
        share: 0.02 to 0.03 % (ZA-12 ingot); 0.012 to 0.02 % (ZA-27 ingot)
        role: A small addition. The Eazall tables give its limits, not its function.
  risk_groups:
    - title: For people
      level: 0
      verdict: Not hazardous as shipped; molten metal burns and fumes
      lead: The Bridesburg SDS says no ingredient qualifies as hazardous under the US Hazard Communication Standard. The risks come when the alloy is melted, burned or cast.
      points:
        - label: The solid alloy
          line: Dust from cutting or grinding is a respiratory hazard, and the SDS says so in its other-hazards list.
        - label: Molten metal
          line: Molten alloy burns the skin and eyes on contact. Eyes should be rinsed immediately with plenty of water (Bridesburg SDS).
        - label: Fume
          line: Melting or burning forms zinc oxide fume. Overheating a molten bath can cause metal fume fever, a transient influenza-like illness (Teck SDS, zinc metal).
    - title: If the melt meets water
      verdict: Violent reaction when molten, with water or moisture
      lead: Water or damp material in a molten bath is the main hazard the sources name. The Bridesburg SDS calls the reaction violent to explosive.
      points:
        - label: Damp ingots
          line: Ingots that may hold moisture must be thoroughly dried before they go into the bath (Teck SDS, zinc metal).
        - label: Fire response
          line: Use dry chemical, dry sand or Class D powder on a metal fire. Do not use water, carbon dioxide or foam on molten metal.
    - title: Handling and storage
      verdict: Dry the charge and wear hot-metal protection
      lead: The SDS practice for molten metal is dry feed, heat-resistant gloves and protective clothing.
      points:
        - label: Feed
          line: Add only dry material to the metal bath (Bridesburg SDS).
        - label: Protection
          line: Where molten metal is involved, wear heat-resistant gloves and suitable protective clothing (Teck SDS).
  why: ZA-12 and ZA-27 are zinc-aluminium casting alloys chosen for bearings and wear parts. Total Materia says both gravity cast alloys are direct substitutes for bronze industrial bearings. Eazall gives typical die cast tensile strengths of 400 MPa for ZA-12 and 421 MPa for ZA-27, and says ZA-27 has excellent bearing and wear performance. The two alloys differ mainly in aluminium content, which is 10.8 to 11.5 % in the ZA-12 ingot and 25.5 to 28.0 % in the ZA-27 ingot (Eazall).
  uses:
    - where: Bearings and bushings
      line: Total Materia describes gravity cast ZA-12 and ZA-27 as direct substitutes for bronze industrial bearings.
    - where: Wear and bearing parts
      line: Eazall says ZA-27 is the lightest alloy available and has excellent bearing and wear performance.
    - where: Weight-bearing castings
      line: Firstmold recommends ZA-12 and ZA-27 where weight-bearing capacity and dimensional stability under load are of prime importance.
  can_do:
    - label: Typical ZA-12 die casting
      line: tensile strength of 400 MPa and yield strength of 317 MPa (Eazall, typical values).
    - label: Typical ZA-27 die casting
      line: tensile strength of 421 MPa and yield strength of 379 MPa (Eazall). The ICAST casting range is 310 to 441 MPa.
    - label: Melting range
      line: Melting range of 377 to 432 °C for ZA-12 and 375 to 484 °C for ZA-27 (Eazall, typical die cast).
    - label: Electrical conductivity
      line: Carry electricity at 28.3 %IACS for ZA-12 and 29.7 %IACS for ZA-27 (Eazall, typical die cast).
  compare: ZA-27 has the higher typical tensile strength, 421 MPa against 400 MPa for ZA-12, and it is the lighter alloy at 5.0 g/cc against 6.0 g/cc in the Eazall tables. ZA-12 stretches more, at 4 to 7 % elongation against 1 to 3 % for ZA-27, and it has the narrower melting range, at 377 to 432 °C against 375 to 484 °C for ZA-27. Firstmold prints a density of 5.6 g/cm3 for ZA-12, so the density of ZA-12 is not settled by the sources read here. The table compares tensile strength, density and melting range.
  compare_rows:
    - label: Tensile strength (typical die casting)
      benchmark: ultimate_tensile_strength
    - label: Density
      benchmark: density
    - label: Melting range
      benchmark: melting_point
  handling:
    - Add only dry material to the metal bath, and dry ingots that may hold moisture before they are added (Bridesburg and Teck SDS).
    - Wear heat-resistant gloves and protective clothing where molten metal is involved (Teck SDS).
    - 'Keep molten metal away from water: use dry chemical, dry sand or Class D powder on a metal fire (Bridesburg SDS).'
  good_for:
    - Bearings and bushings, where Total Materia says ZA alloys can take the place of bronze industrial bearings.
    - Wear parts where Eazall reports excellent bearing and wear performance for ZA-27.
  watch_out:
    - Molten ZA alloy reacts violently with water or moisture, according to the Bridesburg SDS.
    - Melting and overheating release zinc oxide fume, which can cause metal fume fever.
    - Sources disagree on ZA-27 tensile strength (421 MPa typical die cast, 426 MPa in Total Materia, 310 to 441 MPa in ICAST), so check the test form before you design to a number.
  verdict: ZA-12 and ZA-27 are casting alloys with typical die cast figures from Eazall and bearing uses described in the sources read here. Their main hazards come when the alloy is melted, and the sources disagree on several values.