Zinc and zinc alloys Zn

Zn (element · CAS 7440-66-6

Also known as UNS Z33521, UNS Z33531, UNS Z35636, UNS Z35638, ASTM B86 AG40A, ISO ZP3 · 18 more

Zinc (Zn) is used as the coating that galvanises steel, as rolled titanium-zinc sheet for roofs and façades, and as the base of the zinc alloys Zamak 3, Zamak 5 and ZA-8 that are die cast into parts.

20 sources · Updated 2026-10-24 · CC BY 4.0

Evidence level

2 of 5

Lab-measured

Melt

381 to 387 °C (Zamak 3)

Strength, Zamak 3

283 MPa minimum tensile

Strength, Zamak 5

328 MPa minimum tensile

Strength, ZA-8

221 to 374 MPa tensile

Heat conduction

113 W/(m·K) (Zamak 3)

Recipe, share of the weight

  • Zn minimumZinc, pure base of rolled titanium-zinc
  • Cu 0.08 to 0.17%Copper, rolled titanium-zinc
  • Ti 0.07 to 0.12%Titanium, rolled titanium-zinc
  • Al less thanAluminium, rolled titanium-zinc
  • Al 3.7 to 4.3%Aluminium, Zamak 3
  • Mg 0.02 to 0.06%Magnesium, Zamak 3
  • Cu maximumCopper, Zamak 3
  • Fe, Pb, Cd, Sn maximum: Fe 0.05, Pb 0.005, Cd 0.004, Sn 0.002Iron, lead, cadmium and tin, Zamak 3
  • Zn balanceZinc, Zamak 3
  • Al 3.7 to 4.3%Aluminium, Zamak 5
  • Cu 0.7 to 1.2%Copper, Zamak 5
  • Mg 0.02 to 0.06%Magnesium, Zamak 5
  • Fe, Pb, Cd, Sn maximum: Fe 0.05, Pb 0.005, Cd 0.004, Sn 0.002Iron, lead, cadmium and tin, Zamak 5
  • Zn balanceZinc, Zamak 5
  • Al 8 to 8.8%Aluminium, ZA-8
  • Cu 0.8 to 1.3%Copper, ZA-8
  • Mg 0.015 to 0.03%Magnesium, ZA-8
  • Fe, Pb, Cd, Sn maximum: Fe 0.075, Pb 0.006, Cd 0.006, Sn 0.003Iron, lead, cadmium and tin, ZA-8
  • Zn balanceZinc, ZA-8

Best for

Die-cast parts with thin walls, and steel protected by a galvanised zinc coating

Weakest at

Weight (6.3 to 7.2 g/cm3) and post-casting shrinkage in precision die castings

Risk at a glance

  • People Low. Aquatic hazard; some pyrophoric notices
  • If it fails Moderate. Zinc whiskers shorting electronic circuits
  • Corrosion Moderate. Wet, tightly packed galvanised product forms white rust, which is zinc hydroxide.

Quick facts: Zn

Key properties of Zn
PropertyValueBasis
Density6.3 to 7.2 g/cm³5 sourced values across conditions
Yield strength110 to 290 MPa4 sourced values across conditions
Tensile strength150 to 374 MPa4 sourced values across conditions
Hardness (Brinell)82 to 103 HB3 sourced values across conditions
Thermal conductivity109 to 115 W/(m·K)3 sourced values across conditions
Thermal expansion (CTE)22 ppm/K1 sourced value
Melting point375 to 420 °C5 sourced values across conditions
Specific heat419 to 435 J/(kg·K)3 sourced values across conditions

What is the density of Zinc and zinc alloys (Zn)?

Zinc and zinc alloys (Zn) has a density of 6.3 to 7.2 g/cm³. The range covers 5 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What is the thermal conductivity of Zinc and zinc alloys (Zn)?

Zinc and zinc alloys (Zn) has a thermal conductivity of 109 to 115 W/(m·K). The range covers 3 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What is the coefficient of thermal expansion of Zinc and zinc alloys (Zn)?

Zinc and zinc alloys (Zn) has a coefficient of thermal expansion of 22 ppm/K. The source and test conditions are listed in the properties table on this page.

What is the melting point of Zinc and zinc alloys (Zn)?

Zinc and zinc alloys (Zn) has a melting point of 375 to 420 °C. The range covers 5 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What is the yield strength of Zinc and zinc alloys (Zn)?

Zinc and zinc alloys (Zn) has a yield strength of 110 to 290 MPa. The range covers 4 sourced values across the tempers, forms and test conditions the sources report; room-temperature values are used where a source states a temperature.

What are the other names and codes for Zinc and zinc alloys (Zn)?

Zinc and zinc alloys (Zn) is also written as UNS Z33521, UNS Z33531, UNS Z35636, UNS Z35638, ASTM B86 AG40A, ISO ZP3. Each code is printed in the source listed beside it in the designations table.

What is Zinc and zinc alloys (Zn) used for?

Uses recorded in the sources include Silver-zinc battery; Galvanised steel for automobile and construction markets; Rolled titanium-zinc roofs and façades.

Why it exists

Zinc is a metal with a low melting point that does two jobs. As a coating it protects steel: the zinc forms a carbonate film that slows its own corrosion, and galvanising extends the life of steel because that film behaves differently from iron oxide. As a die-casting alloy it is cast into parts, and Dynacast lists a lower melting point, excellent thin-wall capability and high dimensional accuracy for zinc die casting. Zamak 3 is the most widely used zinc alloy in North America and Zamak 5 in Europe, and ZA-8 is the aluminium-rich member of the family. Zinc metal melts at 419.53 °C and has a density of 7.133 g/cm3 at 25 °C, while Zamak 3 melts over 381 to 387 °C.

Where it's used

Batteries

Silver-zinc batteries powered several early NASA spacecraft, including the Apollo command module, according to NASA's 2016 article.

Galvanised steel

Galvanised steel was the leading use of refined zinc in the United States, used widely in automobile and construction markets (USGS, 2025).

Die castings

The ASTM B86 sheets from ICAST give valve, pump, general engineering and automotive parts as the intended use of Zamak 3, Zamak 5 and ZA-8.

Heat sinks and EMI shielding

The International Zinc Association says zinc diecasting alloys conduct heat and electricity well, which suits heat sinks, wave-guides and EMI shielding.

Roofs and façades

NedZink sells rolled titanium-zinc for standing-seam and roll-cap roofs and standing-seam façades, and describes it as weather-resistant and maintenance-free.

Recipe

Zn (element; CAS 7440-66-6). Zamak 3, ASTM B86 AG40A (weight %): Al 3.7 to 4.3, Mg 0.02 to 0.06, Cu 0.1 max, Fe 0.05 max, Pb 0.005 max, Cd 0.004 max, Sn 0.002 max, Zn balance. Zamak 5, ASTM B86 AC41A (weight %): Al 3.7 to 4.3, Cu 0.7 to 1.2, Mg 0.02 to 0.06, Fe 0.05 max, Pb 0.005 max, Cd 0.004 max, Sn 0.002 max, Zn balance. ZA-8, UNS Z35636 (weight %): Al 8.0 to 8.8, Cu 0.8 to 1.3, Mg 0.015 to 0.03, Fe 0.075 max, Pb 0.006 max, Cd 0.006 max, Sn 0.003 max, Zn balance; the ASTM B86 ZA-8 sheet prints Mg 0.01 to 0.03 and the Wikipedia casting column prints 0.015 to 0.03. Rolled titanium-zinc (NedZink, weight %): Zn 99.995 minimum, Cu 0.08 to 0.17, Ti 0.07 to 0.12, Al below 0.015.

Pure zinc is the element Zn. The die-casting alloys add aluminium with smaller amounts of copper and magnesium: Zamak 3 (ASTM B86 AG40A) has 3.7 to 4.3 % aluminium and 0.02 to 0.06 % magnesium; Zamak 5 (ASTM B86 AC41A) also has 0.7 to 1.2 % copper; ZA-8 (UNS Z35636) has 8.0 to 8.8 % aluminium and 0.8 to 1.3 % copper. Rolled titanium-zinc sheet from NedZink is at least 99.995 % zinc with small additions of copper, titanium and aluminium. Each alloy is zinc for the balance. The sources reviewed do not describe the smelting or casting steps, so none are given here.

What Zn is made of
IngredientShare of the weightWhat it does
Zinc, pure base of rolled titanium-zinc Zn minimum Base metal of the NedZink rolled product (Z1 under EN 1179)
Copper, rolled titanium-zinc Cu 0.08 to 0.17% Small alloying addition
Titanium, rolled titanium-zinc Ti 0.07 to 0.12% Small alloying addition
Aluminium, rolled titanium-zinc Al less than Small addition, kept low
Aluminium, Zamak 3 Al 3.7 to 4.3% Main alloying element
Magnesium, Zamak 3 Mg 0.02 to 0.06% Minor alloying element (ASTM B86 range)
Copper, Zamak 3 Cu maximum Impurity limit
Iron, lead, cadmium and tin, Zamak 3 Fe, Pb, Cd, Sn maximum: Fe 0.05, Pb 0.005, Cd 0.004, Sn 0.002 Impurity limits
Zinc, Zamak 3 Zn balance Matrix
Aluminium, Zamak 5 Al 3.7 to 4.3% Main alloying element
Copper, Zamak 5 Cu 0.7 to 1.2% Copper addition (ASTM B86 AC41A range)
Magnesium, Zamak 5 Mg 0.02 to 0.06% Minor alloying element (ASTM B86 range)
Iron, lead, cadmium and tin, Zamak 5 Fe, Pb, Cd, Sn maximum: Fe 0.05, Pb 0.005, Cd 0.004, Sn 0.002 Impurity limits
Zinc, Zamak 5 Zn balance Matrix
Aluminium, ZA-8 Al 8 to 8.8% Main alloying element; Dynacast gives about 8.4 % and says ZA-8 is the only ZA alloy that can be hot-chamber die cast
Copper, ZA-8 Cu 0.8 to 1.3% Copper addition
Magnesium, ZA-8 Mg 0.015 to 0.03% Minor alloying element (UNS Z35636 range; the ASTM B86 ZA-8 sheet prints 0.01 to 0.03)
Iron, lead, cadmium and tin, ZA-8 Fe, Pb, Cd, Sn maximum: Fe 0.075, Pb 0.006, Cd 0.006, Sn 0.003 Impurity limits
Zinc, ZA-8 Zn balance Matrix

Weight shares are as printed in the sources.

What it can do

Melt

381 to 387 °C (Zamak 3)

Zamak 3 melts over 381 to 387 °C, Zamak 5 over 380 to 386 °C and ZA-8 over 375 to 404 °C, according to the IZA table.

Strength, Zamak 3

283 MPa minimum tensile

The ASTM B86 AG40A limits require at least 283 MPa tensile strength, 221 MPa yield strength and 10 % elongation, in the as-cast or aged condition.

Strength, Zamak 5

328 MPa minimum tensile

The ASTM B86 AC41A limits require at least 328 MPa tensile strength and 228 MPa yield strength, with 7 % elongation.

Strength, ZA-8

221 to 374 MPa tensile

ZA-8 is printed at 221 to 374 MPa tensile strength and 198 to 290 MPa yield strength, with 1 to 10 % elongation and 85 to 103 HB hardness.

Heat conduction

113 W/(m·K) (Zamak 3)

Thermal conductivity at 70 to 140 °C is 113 W/(m·K) for Zamak 3, 108.9 for Zamak 5 and 114.7 for ZA-8 (IZA).

Weight

6.3 to 7.2 g/cm3 across the family

Density is 6.6 g/cm3 for Zamak 3 and 6.3 g/cm3 for ZA-8 (zero porosity, 21 °C), and 7.133 g/cm3 for pure zinc at 25 °C.

Rolled sheet

150 N/mm2 minimum tensile

Rolled titanium-zinc has a minimum tensile strength of 150 N/mm2 and a minimum elongation of 40 % (NedZink product requirements).

Dimensional change

0.03 % after 2 years

Zamak 3 castings that have been stabilised contract by 0.02 % after 5 weeks and 0.03 % after 2 years (IZA).

How it compares

Among the die-casting alloys, Zamak 3 and Zamak 5 are close in density (6.6 and 6.76 g/cm3) and in thermal conductivity (113 and 108.9 W/(m·K)). Zamak 5 has the higher minimum strength (328 MPa tensile and 228 MPa yield, against 283 and 221 for Zamak 3) but the lower minimum elongation (7 %, against 10 %). ZA-8 is the lightest of the three at 6.3 g/cm3, and its tensile range runs to 374 MPa, but its elongation runs from 1 to 10 %. Pure zinc is denser at 7.133 g/cm3 at 25 °C, and the rolled titanium-zinc sheet is weaker in tension, with a minimum of 150 N/mm2.

The same measurements for each material, so you can compare them. Each row names the key condition under the value; the full conditions and methods are in the numbered notes under Technical details. Other materials are shown beside it; each was measured under its own conditions, so open its page before comparing closely. Compare every grade in the family.

Benchmarks
MeasurementZnZamakZn minor alloys
Thermal behavior and safety
Melting point, pure zinc (element)419.5 °C2381 to 387 °C420 °C
Melting point, rolled titanium-zinc (NedZink)420 °C5381 to 387 °C420 °C
Thermal conductivity, Zamak 3 (ZP3)113 W/(m·K)17113 W/(m·K)109 W/m °K
Specific heat capacity, Zamak 3 (ZP3)418.7 J/(kg·K)18418.7 J/(kg·K)no data
Melting temperature range, Zamak 3 (ZP3)381 to 387 °C20381 to 387 °C420 °C
Thermal conductivity, Zamak 5 (ZP5)108.9 W/(m·K)29113 W/(m·K)109 W/m °K
Specific heat capacity, Zamak 5 (ZP5)418.7 J/(kg·K)30418.7 J/(kg·K)no data
Melting temperature range, Zamak 5 (ZP5)380 to 386 °C32381 to 387 °C420 °C
Thermal conductivity, ZA-8 (ZP8)114.7 W/(m·K)41113 W/(m·K)109 W/m °K
Specific heat capacity, ZA-8 (ZP8)435.4 J/(kg·K)42418.7 J/(kg·K)no data
Melting temperature range, ZA-8 (ZP8)375 to 404 °C44381 to 387 °C420 °C
Physical and electrical
Density, pure zinc (element)7.133 g/cm³1no data7.2 g/cm³
Density, rolled titanium-zinc (NedZink)7.2 g/cm³4no data7.2 g/cm³
Hardness minimum, Zamak 3 (ASTM B86 AG40A)> 82 HB14> 82 HBno data
Specific gravity, Zamak 3 (ZP3), zero porosity6.6 g/cm³15no data7.2 g/cm³
Electrical conductivity, Zamak 3 (ZP3)27 % IACS1927 % IACSno data
Hardness minimum, Zamak 5 (ASTM B86 AC41A)> 91 HB26> 82 HBno data
Specific gravity, Zamak 5 (ZP5), zero porosity6.76 g/cm³27no data7.2 g/cm³
Electrical conductivity, Zamak 5 (ZP5)27.2 % IACS3127 % IACSno data
Hardness range, ZA-8 (ASTM B86 ZA-8)85 to 103 HB38> 82 HBno data
Specific gravity, ZA-8 (ZP8), zero porosity6.3 g/cm³39no data7.2 g/cm³
Electrical conductivity, ZA-8 (ZP8)27.4 % IACS4327 % IACSno data
Temperature behavior
Recrystallisation temperature, rolled titanium-zinc (NedZink)> 300 °C6no datano data
Other measurements
Boiling point, pure zinc (element)907 °C3no datano data
Linear expansion coefficient, rolled titanium-zinc (NedZink)0.022 mm/(mK)727 µm/m/°C0.022 mm/m °C
Yield strength Rp0.2, rolled titanium-zinc (product minimum)> 110 N/mm28> 221 MPa> 100 N/mm2
Tensile strength Rm, rolled titanium-zinc (product minimum)> 150 N/mm29> 283 MPa> 150 N/mm2
Elongation A50, rolled titanium-zinc (product minimum)> 40 %10> 10 %> 35 %
Tensile strength minimum, Zamak 3 (ASTM B86 AG40A)> 283 MPa11> 283 MPa> 150 N/mm2
Yield strength minimum, Zamak 3 (ASTM B86 AG40A)> 221 MPa12> 221 MPa> 100 N/mm2
Elongation minimum, Zamak 3 (ASTM B86 AG40A)> 10 %13> 10 %> 35 %
Thermal expansion, Zamak 3 (ZP3)27 µm/m/°C1627 µm/m/°C0.022 mm/m °C
Post-casting contraction, Zamak 3, 5 weeks after stabilisation0.02 %210.02 %no data
Post-casting contraction, Zamak 3, 2 years after stabilisation0.03 %220.02 %no data
Tensile strength minimum, Zamak 5 (ASTM B86 AC41A)> 328 MPa23> 283 MPa> 150 N/mm2
Yield strength minimum, Zamak 5 (ASTM B86 AC41A)> 228 MPa24> 221 MPa> 100 N/mm2
Elongation minimum, Zamak 5 (ASTM B86 AC41A)> 7 %25> 10 %> 35 %
Thermal expansion, Zamak 5 (ZP5)27.2 µm/m/°C2827 µm/m/°C0.022 mm/m °C
Post-casting contraction, Zamak 5, 5 weeks after stabilisation0.021 %330.02 %no data
Post-casting contraction, Zamak 5, 2 years after stabilisation0.037 %340.02 %no data
Tensile strength range, ZA-8 (ASTM B86 ZA-8)221 to 374 MPa35> 283 MPa> 150 N/mm2
Yield strength range, ZA-8 (ASTM B86 ZA-8)198 to 290 MPa36> 221 MPa> 100 N/mm2
Elongation range, ZA-8 (ASTM B86 ZA-8)1 to 10 %37> 10 %> 35 %
Thermal expansion, ZA-8 (ZP8)27.3 µm/m/°C4027 µm/m/°C0.022 mm/m °C

Why choose it, and why not

Good for

  • Die-cast parts with thin walls and complex shapes (Dynacast lists excellent thin-wall capability).
  • Heat sinks and EMI shielding from zinc diecastings, where conductivity counts (IZA).
  • Weather-resistant roofing and façades in rolled titanium-zinc (NedZink).
  • Silver-zinc batteries, which powered early NASA spacecraft such as Apollo (NASA).

Watch out for

  • Heavy: 6.3 to 7.2 g/cm3 depending on the grade.
  • Some notifications classify zinc as pyrophoric (H250) and say contact with water releases flammable gas (H260).
  • Wet storage forms white rust, a zinc hydroxide stain that can remove some coating.
  • Zinc whiskers have caused electronic failures in NASA's whisker failure list.
  • Die castings shrink after casting; stabilise precision parts (IZA).
  • Sources differ for the same grade: the ICAST UNS Z33521 sheet gives lower minimum tensile and yield strengths for Zamak 3 than the ASTM B86 AG40A sheet, so confirm limits against the standard.
  • No vacuum, outgassing or radiation data for zinc alloys were found in this run.

Zinc and its die-casting alloys are well documented and cast well into thin, complex parts, and the metal protects steel as a coating. Zamak 3 and Zamak 5 are the common choices, ZA-8 has the widest strength range and the least ductility, and zinc powder is a fire hazard. This profile has no space-environment data for zinc or its alloys.

Technical details

For scientists and researchers. Everything above comes from the record below: every number with its method, its conditions and its source.

Other names and standards

The same grade under other systems, as datasheets and standards print them. Each code was checked against the page it comes from.

Other names and standards
SystemCodes
UNSZ33521 (AG40A ingot), Z33531, Z35636, Z35638 (also printed)
ASTMB86 AG40A, B240 Zamak 3, B86 AC41A, B240 AC41A, B86 ZA-8, B69
ISOZP3, ZP5, ZP8, ZP0810
UNIZnAl4
EN988, 1179 (Z1 grade)
NameZamak 3, Zinc Alloy 3, Zamak 5, Zinc Alloy 5, ZA-8, Special High Grade (SHG zinc)
Trade nameNedZink titanium zinc

Notes

The method, full conditions and any caveat for the numbered rows above.

Notes for the numbered rows
#MeasurementMethodConditionsCaveat
1Density, pure zinc (element)Value printed in the Density section of the PubChem record for zinc (CID 23994)alloy pure zinc (element)condition form not stated in the PubChem recordtemperature 25 °Cunit in source g/cu cm—
2Melting point, pure zinc (element)Value printed in the Melting Point section of the PubChem record for zinc (CID 23994)alloy pure zinc (element)condition form not stated in the PubChem recordunit in source 419.53 °C—
3Boiling point, pure zinc (element)Value printed in the Boiling Point section of the PubChem record for zinc (CID 23994)alloy pure zinc (element)condition at 760 mm Hgunit in source 907 °C @760 [mm Hg]—
4Density, rolled titanium-zinc (NedZink)Value printed in the physical properties table of the NedZink technical specification (English page)alloy rolled titanium-zinc (NedZink; Zn 99.995 % base with small Cu, Ti and Al additions)condition rolled sheet, manufacturer's physical property tableunit in source g/cm3—
5Melting point, rolled titanium-zinc (NedZink)Value printed in the physical properties table of the NedZink technical specification (English page)alloy rolled titanium-zinc (NedZink; Zn 99.995 % base with small Cu, Ti and Al additions)condition rolled sheet, manufacturer's physical property tableunit in source °C—
6Recrystallisation temperature, rolled titanium-zinc (NedZink)Lower limit printed in the physical properties table of the NedZink technical specificationalloy rolled titanium-zinc (NedZink; Zn 99.995 % base with small Cu, Ti and Al additions)condition rolled sheetreading printed as a lower limit, '> 300 °C'Custom benchmark name, not in property-canon.yaml; printed as a lower limit only.
7Linear expansion coefficient, rolled titanium-zinc (NedZink)Value printed as 0.022 mm/(mK), that is millimetres per metre per kelvin; the importer converts it to ppm/K (0.022 mm/(m·K) equals 22 ppm/K)alloy rolled titanium-zinc (NedZink; Zn 99.995 % base with small Cu, Ti and Al additions)condition rolled sheetunit in source mm/(mK)equivalent 22 ppm/K—
8Yield strength Rp0.2, rolled titanium-zinc (product minimum)Minimum product requirement printed in the mechanical and technological properties table of the NedZink specificationalloy rolled titanium-zinc (NedZink; Zn 99.995 % base with small Cu, Ti and Al additions)condition rolled sheet; product requirement (minimum)test Rp 0,2 (yield strength)unit in source N/mm2A minimum product requirement, not a typical test result.
9Tensile strength Rm, rolled titanium-zinc (product minimum)Minimum product requirement printed in the mechanical and technological properties table of the NedZink specificationalloy rolled titanium-zinc (NedZink; Zn 99.995 % base with small Cu, Ti and Al additions)condition rolled sheet; product requirement (minimum)test tensile strength Rmunit in source N/mm2A minimum product requirement, not a typical test result.
10Elongation A50, rolled titanium-zinc (product minimum)Minimum product requirement printed in the mechanical and technological properties table of the NedZink specificationalloy rolled titanium-zinc (NedZink; Zn 99.995 % base with small Cu, Ti and Al additions)condition rolled sheet; product requirement (minimum)test elongation A50A minimum product requirement; the Vickers hardness row prints 'min. 40%' with no clear unit and is not recorded.
11Tensile strength minimum, Zamak 3 (ASTM B86 AG40A)Minimum limit printed in the mechanical properties block of the ICAST copy of ASTM B86 AG40A; not a typical test valuealloy Zamak 3 (ASTM B86 AG40A; ZP3; UNS Z33521)condition as-cast or aging (heat-treatment column of the sheet)unit in source MpaThe ICAST UNS Z33521 sheet prints 280 MPa minimum for the same grade; the two ICAST sheets are not identical and this record uses the ASTM B86 AG40A sheet.
12Yield strength minimum, Zamak 3 (ASTM B86 AG40A)Minimum limit printed in the mechanical properties block of the ICAST copy of ASTM B86 AG40A; not a typical test valuealloy Zamak 3 (ASTM B86 AG40A; ZP3; UNS Z33521)condition as-cast or aging (heat-treatment column of the sheet)unit in source MpaThe ICAST UNS Z33521 sheet prints 200 MPa minimum for the same grade.
13Elongation minimum, Zamak 3 (ASTM B86 AG40A)Minimum limit printed in the mechanical properties block of the ICAST copy of ASTM B86 AG40A; not a typical test valuealloy Zamak 3 (ASTM B86 AG40A; ZP3; UNS Z33521)condition as-cast or aging (heat-treatment column of the sheet)—
14Hardness minimum, Zamak 3 (ASTM B86 AG40A)Minimum limit printed in the mechanical properties block of the ICAST copy of ASTM B86 AG40A; not a typical test valuealloy Zamak 3 (ASTM B86 AG40A; ZP3; UNS Z33521)condition as-cast or aging (heat-treatment column of the sheet)Custom benchmark name, not in property-canon.yaml. The ICAST UNS Z33521 sheet prints 83 HB minimum.
15Specific gravity, Zamak 3 (ZP3), zero porosityValue printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 3 (ZP3)condition die-cast alloy, zero porositytemperature 21 °Cunit in source specific gravity (no unit printed)—
16Thermal expansion, Zamak 3 (ZP3)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 3 (ZP3)condition die-cast alloytemperature 20 to 100 °Cunit in source µm/m/°C—
17Thermal conductivity, Zamak 3 (ZP3)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 3 (ZP3)condition die-cast alloytemperature 70 to 140 °Cunit in source W m-1 °C-1—
18Specific heat capacity, Zamak 3 (ZP3)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 3 (ZP3)condition die-cast alloytemperature 20 to 100 °Cunit in source J/kg/°C—
19Electrical conductivity, Zamak 3 (ZP3)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 3 (ZP3)condition die-cast alloytemperature not statedCustom benchmark name, not in property-canon.yaml.
20Melting temperature range, Zamak 3 (ZP3)Range printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 3 (ZP3)condition die-cast alloyreading melting temperature range, solidus to liquidus—
21Post-casting contraction, Zamak 3, 5 weeks after stabilisationContraction printed in the Dimensional Stability As Stabilised table of the International Zinc Association guidealloy Zamak 3 (ZP3)condition aged: stabilised (3 to 6 h at 100 °C, or 5 to 10 h at 85 °C, or 10 to 20 h at 70 °C), then measured after 5 weeksreading contraction as stabilisedCustom benchmark name, not in property-canon.yaml. Shows the aged (stabilised) condition.
22Post-casting contraction, Zamak 3, 2 years after stabilisationContraction printed in the Dimensional Stability As Stabilised table of the International Zinc Association guidealloy Zamak 3 (ZP3)condition aged: stabilised (3 to 6 h at 100 °C, or 5 to 10 h at 85 °C, or 10 to 20 h at 70 °C), then measured after 2 yearsreading contraction as stabilisedCustom benchmark name, not in property-canon.yaml. Shows the aged (stabilised) condition.
23Tensile strength minimum, Zamak 5 (ASTM B86 AC41A)Minimum limit printed in the mechanical properties block of the ICAST copy of ASTM B86 AC41A; not a typical test valuealloy Zamak 5 (ASTM B86 AC41A; ZP5; UNS Z33531 as printed)condition as-cast or aging (heat-treatment column of the sheet)unit in source Mpa—
24Yield strength minimum, Zamak 5 (ASTM B86 AC41A)Minimum limit printed in the mechanical properties block of the ICAST copy of ASTM B86 AC41A; not a typical test valuealloy Zamak 5 (ASTM B86 AC41A; ZP5; UNS Z33531 as printed)condition as-cast or aging (heat-treatment column of the sheet)unit in source Mpa—
25Elongation minimum, Zamak 5 (ASTM B86 AC41A)Minimum limit printed in the mechanical properties block of the ICAST copy of ASTM B86 AC41A; not a typical test valuealloy Zamak 5 (ASTM B86 AC41A; ZP5; UNS Z33531 as printed)condition as-cast or aging (heat-treatment column of the sheet)—
26Hardness minimum, Zamak 5 (ASTM B86 AC41A)Minimum limit printed in the mechanical properties block of the ICAST copy of ASTM B86 AC41A; not a typical test valuealloy Zamak 5 (ASTM B86 AC41A; ZP5; UNS Z33531 as printed)condition as-cast or aging (heat-treatment column of the sheet)Custom benchmark name, not in property-canon.yaml.
27Specific gravity, Zamak 5 (ZP5), zero porosityValue printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 5 (ZP5)condition die-cast alloy, zero porositytemperature 21 °Cunit in source specific gravity (no unit printed)—
28Thermal expansion, Zamak 5 (ZP5)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 5 (ZP5)condition die-cast alloytemperature 20 to 100 °Cunit in source µm/m/°C—
29Thermal conductivity, Zamak 5 (ZP5)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 5 (ZP5)condition die-cast alloytemperature 70 to 140 °Cunit in source W m-1 °C-1—
30Specific heat capacity, Zamak 5 (ZP5)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 5 (ZP5)condition die-cast alloytemperature 20 to 100 °Cunit in source J/kg/°C—
31Electrical conductivity, Zamak 5 (ZP5)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 5 (ZP5)condition die-cast alloytemperature not statedCustom benchmark name, not in property-canon.yaml.
32Melting temperature range, Zamak 5 (ZP5)Range printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy Zamak 5 (ZP5)condition die-cast alloyreading melting temperature range, solidus to liquidus—
33Post-casting contraction, Zamak 5, 5 weeks after stabilisationContraction printed in the Dimensional Stability As Stabilised table of the International Zinc Association guidealloy Zamak 5 (ZP5)condition aged: stabilised (3 to 6 h at 100 °C, or 5 to 10 h at 85 °C, or 10 to 20 h at 70 °C), then measured after 5 weeksreading contraction as stabilisedCustom benchmark name, not in property-canon.yaml. Shows the aged (stabilised) condition.
34Post-casting contraction, Zamak 5, 2 years after stabilisationContraction printed in the Dimensional Stability As Stabilised table of the International Zinc Association guidealloy Zamak 5 (ZP5)condition aged: stabilised (3 to 6 h at 100 °C, or 5 to 10 h at 85 °C, or 10 to 20 h at 70 °C), then measured after 2 yearsreading contraction as stabilisedCustom benchmark name, not in property-canon.yaml. Shows the aged (stabilised) condition.
35Tensile strength range, ZA-8 (ASTM B86 ZA-8)Range printed in the mechanical properties block of the ICAST copy of ASTM B86 ZA-8; not a typical test valuealloy ZA-8 (ASTM B86 ZA-8; UNS Z35636; ZP8)condition as-cast or aging (heat-treatment column of the sheet)unit in source MpaThe ICAST UNS Z35636 sheet prints the same mechanical ranges.
36Yield strength range, ZA-8 (ASTM B86 ZA-8)Range printed in the mechanical properties block of the ICAST copy of ASTM B86 ZA-8; not a typical test valuealloy ZA-8 (ASTM B86 ZA-8; UNS Z35636; ZP8)condition as-cast or aging (heat-treatment column of the sheet)unit in source Mpa—
37Elongation range, ZA-8 (ASTM B86 ZA-8)Range printed in the mechanical properties block of the ICAST copy of ASTM B86 ZA-8; not a typical test valuealloy ZA-8 (ASTM B86 ZA-8; UNS Z35636; ZP8)condition as-cast or aging (heat-treatment column of the sheet)—
38Hardness range, ZA-8 (ASTM B86 ZA-8)Range printed in the mechanical properties block of the ICAST copy of ASTM B86 ZA-8; not a typical test valuealloy ZA-8 (ASTM B86 ZA-8; UNS Z35636; ZP8)condition as-cast or aging (heat-treatment column of the sheet)Custom benchmark name, not in property-canon.yaml.
39Specific gravity, ZA-8 (ZP8), zero porosityValue printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy ZA-8 (ZP8)condition die-cast alloy, zero porositytemperature 21 °Cunit in source specific gravity (no unit printed)—
40Thermal expansion, ZA-8 (ZP8)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy ZA-8 (ZP8)condition die-cast alloytemperature 20 to 100 °Cunit in source µm/m/°C—
41Thermal conductivity, ZA-8 (ZP8)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy ZA-8 (ZP8)condition die-cast alloytemperature 70 to 140 °Cunit in source W m-1 °C-1—
42Specific heat capacity, ZA-8 (ZP8)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy ZA-8 (ZP8)condition die-cast alloytemperature 20 to 100 °Cunit in source J/kg/°C—
43Electrical conductivity, ZA-8 (ZP8)Value printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy ZA-8 (ZP8)condition die-cast alloytemperature not statedCustom benchmark name, not in property-canon.yaml.
44Melting temperature range, ZA-8 (ZP8)Range printed in the physical properties table of the International Zinc Association die-casting alloy guidealloy ZA-8 (ZP8)condition die-cast alloyreading melting temperature range, solidus to liquidus—

Corrosion and compatibility

What happens when it meets other materials and environments.

Corrosion and compatibility
EnvironmentConcernWhat happens
Wet storage of galvanised coil, sheet and pack moderate Wet, tightly packed galvanised product forms white rust, which is zinc hydroxide.1
Open air, non-marine (galvanised steel and zinc surfaces) low In open air a zinc carbonate film forms during drying and slows further corrosion.2
Chloride-laden or marine air moderate Chloride salts speed white rust and loss of zinc.3
Corrosion details
#EnvironmentDetailsTest conditions
1 Wet storage of galvanised coil, sheet and pack Storage stain (usually white rust) is zinc hydroxide, which forms when zinc is in contact with moisture. It does not convert to the protective carbonate film, because wet packs starve the surface of oxygen and carbon dioxide. The extent depends on the time wet, the temperature and chloride-containing salts. When white rust occurs there is an actual loss of zinc coating, although most of it can be removed with no significant long-term damage to the coating. exposure wet packs, coils or tubes in storage or transportaccelerants moisture; chloride-containing saltsbasis qualitative statements, no measured rate
2 Open air, non-marine (galvanised steel and zinc surfaces) Zinc reacts with oxygen to a thin oxide, then with water to zinc hydroxide, and over time with carbon dioxide to zinc carbonate, the tenacious film that protects the surface. That film forms only when the surface dries between wet spells. GalvInfoNote 3.2 puts the corrosion rate of a zinc coating at anywhere from 10 to 100 times slower than bare steel. basis mechanism and a relative rate (10 to 100 times slower than bare steel); no corrosion rate in micrometres per yearenvironment note atmosphere with wet-dry cycles
3 Chloride-laden or marine air Both sources name chloride-containing salts as accelerating corrosive agents for white rust. The steel.org.au note says zinc has a low atmospheric corrosion rate in non-marine environments only because a continuous passive film forms, so marine exposure is a different case. basis qualitative statements, no measured rateagent chloride-containing salts

Risks and side effects

Hazards to people, what happens when a cell overheats, and how the material is handled and stored.

For people

The sources give no occupational exposure limit for zinc. The hazards on record are mainly to aquatic life, with a fire risk in some pyrophoric notifications.

Notified classes
Of the 2,237 reports that give hazard codes, 84.9 % list very toxic to aquatic life (H400) and 79 % list very toxic to aquatic life with long lasting effects (H410). Of all 2,624 reports, 14.7 % (387) say zinc does not meet GHS criteria.
Pyrophoric notices
Some notifications classify zinc as pyrophoric: H250 (26.7 % of reports giving codes) says it catches fire spontaneously if exposed to air, and H260 (26.7 %) says contact with water releases flammable gases.
Eyes
One notification block lists H320, causes eye irritation, with the Warning signal word.

If it fails

These failure routes come from the sources. They are field reports and standards notes, not space tests.

Zinc whiskers
NASA's whisker failure list cites a 1994 rotary-switch failure attributed to zinc whiskers and a 2006 private communication on zinc whiskers in relays. It also attributes system failures to zinc whiskers from raised access floor tiles.
White rust
Wet, tightly packed galvanised product forms white rust, which is zinc hydroxide. The stain etches the coating and can remove some zinc, although most white rust can be removed without lasting damage.
Dimensional change
Die castings keep shrinking after casting. The IZA says the change is negligible for most purposes, and a stabilising heat treatment brings most of it forward.

Handling and storage

Keep dust and powder dry
Keep zinc dust and powder away from water: some notifications say contact releases flammable gas (ECHA notifications via PubChem).
Keep packs dry
Open and dry wet packs of galvanised product, use dry dunnage and keep tarpaulins dry (steel.org.au).
Stabilise precision parts
Hold castings for 3 to 6 hours at 100 °C, or 5 to 10 hours at 85 °C, or 10 to 20 hours at 70 °C (IZA).

Test details
The original wording and numbers from the sources, for readers who want them.

Failure risks

Failure risks
FailureTrigger and consequence
Zinc whiskers shorting electronic circuitsmoderate severityZinc-plated or zinc surfaces in electronic systems, including raised access floor tiles and relaysNASA's whisker failure list cites a 1994 rotary-switch failure attributed to zinc whiskers (J. Downs, Metal Finishing), a 2006 private communication on zinc whiskers in relays, and system failures attributed to zinc whiskers from raised access floor tiles in computer servers, routers and power supplies.
White rust removing zinc coating in storagelow severityWet, tightly packed galvanised product in storage or transportAn actual loss of zinc coating occurs when white rust forms, and the surface is etched and loses its bright appearance.
Post-casting shrinkage of die castingslow severityDie castings left at ambient temperature after casting, without stabilisationPost-casting shrinkage continues after casting. The IZA gives contraction after stabilisation of 0.02 % at 5 weeks and 0.03 % at 2 years for Zamak 3; for high-precision parts this may need to be taken into account.

Side effects on surrounding parts

Side effects on surrounding parts
AffectsEffect
Waterways and aquatic life near zinc releasesThe hazard codes most often notified are very toxic to aquatic life (H400, 84.9 % of reports giving codes) and very toxic to aquatic life with long lasting effects (H410, 79 % of reports giving codes).

Handling and storage

  • Keep zinc dust and powder dry and away from water. The aggregated PubChem record gives H260: in contact with water releases flammable gases, which may ignite spontaneously.
  • Keep galvanised coil, sheet and tube dry and separated. Open wet packs and let them dry, use dry dunnage, and keep tarpaulins dry so that water stays out of the load.
  • Stabilise precision castings: 3 to 6 hours at 100 °C, or 5 to 10 hours at 85 °C, or 10 to 20 hours at 70 °C.

Mitigations

  • Passivation treatments reduce white rust, but do not prevent it in improper storage. Chromium-based treatments were historically used and are being replaced by silane or trivalent chromium treatments.
  • The stabilisation heat treatment brings forward shrinkage that would otherwise happen slowly after casting.

Supply and geography

How common the raw materials are and where they come from.

Zinc

Identified zinc resources of the world are about 1.9 billion tons; world reserves are 240,000 thousand t (USGS MCS 2026, zinc content)

Top producers (2025)
China 31.5%, Peru 11.5%, Australia 8.5%, India 6.7%, Mexico 6%
Critical mineral lists
US: listed
Recycling
USGS: refined zinc is recovered from secondary materials at primary and secondary smelters, including galvanizing residues and crude zinc oxide from electric arc furnace dust. Net import reliance for refined zinc was 73 % in 2025 (estimated).
Substitutes
USGS: aluminum and plastics substitute for galvanized sheet in automobiles; aluminum alloys, cadmium, paint and plastic coatings replace zinc coatings in other applications; aluminum- and magnesium-base alloys are major substitutes for zinc-base diecasting alloys.