Zinc Alloy ZA-8 · print state
Zinc Alloy ZA-8 Sand Cast
Properties of the Sand Cast condition, compared with the other ZA-8 tempers.
Choose for low-volume, larger or thick-section parts; slower solidification lowers strength and especially ductility versus die cast.
What is ZA-8 Sand Cast?
ZA-8 Sand Cast is ZA-8 in the Sand Cast condition — choose for low-volume, larger or thick-section parts; slower solidification lowers strength and especially ductility versus die cast. ZA-8 Sand Cast has a yield strength of 200 MPa (29 ksi) and a tensile strength of 250 MPa (36.3 ksi) — stronger than 57% of zinc alloy grades. Elongation at break is 1.5% and the elastic modulus is 85.5 GPa (12.4 Msi). ZA-8 Sand Cast has a density of 6.3 g/cm³ (0.228 lb/in³), lighter than 86% of zinc alloy grades. It melts at 375°C (707 °F). As Cast is the default condition FabDigit quotes; Sand Cast is available on request or by drawing note.
Limitations
- Limited ductility — 1.5%, worse than 100% of zinc alloy grades
ZA-8 Sand Cast properties
Typical room-temperature values for ZA-8 Sand Cast — 9 properties are specific to this condition; the rest are grade-level values shared by every ZA-8 temper. Each bar shows where the value sits among the zinc alloy grades in FabDigit's library — further right is higher.
Physical3
ZA-8 Sand Cast has a density of 6.3 g/cm³ (0.228 lb/in³), lighter than 86% of zinc alloy grades. It melts at 375°C (707 °F).
Mechanical12
ZA-8 Sand Cast has a yield strength of 200 MPa (29 ksi) and a tensile strength of 250 MPa (36.3 ksi) — stronger than 57% of zinc alloy grades. Elongation at break is 1.5% and the elastic modulus is 85.5 GPa (12.4 Msi).
Thermal6
ZA-8 Sand Cast is rated for continuous service to 100°C (212 °F). It conducts heat at 114.7 W/m·K (66.3 BTU/hr·ft·°F), better than 71% of zinc alloy grades. Thermal expansion is 23.3 µm/m·K (12.9 µin/in·°F).
Electrical3
ZA-8 Sand Cast conducts electricity at 27.7 % IACS, better than 64% of zinc alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (45/100), better than 82% of zinc alloy grades.
Sustainability4
Producing a kilogram of ZA-8 Sand Cast takes about 57 MJ of energy and emits 4 kg of CO₂ — more than 86% of zinc alloy grades. Typical recycled content is 35%.
Manufacturability7
ZA-8 Sand Cast's machinability is very good (82/100, better than 86% of zinc alloy grades); weldability poor (20/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other ZA-8 tempers and conditions
ZA-8 is also supplied in 4 other conditions. The full side-by-side table is on the ZA-8 overview.
- As CastDefaultDefault commercial condition: thin-wall hot-chamber die castings with the highest strength and hardness of the ZA-8 forms.290 MPa yield · 100 HB
- DIEHot-chamber pressure die cast ZA-8 (ASTM B86 / UNS Z35636): fine chill-cast structure giving the highest strength and hardness of the as-cast ZA-8 conditions.290 MPa yield · 103 HB
- PM CastMid-volume gravity casting route giving finer structure and better properties than sand cast, below die-cast levels.207 MPa yield · 88 HB
- Sand CastChoose for low-volume, larger or thick-section parts; slower solidification lowers strength and especially ductility versus die cast.200 MPa yield · 85 HB
Working with ZA-8 Sand Cast
Is ZA-8 easy to machine?
Machines very easily with sharp positive-rake carbide or HSS tools, high speeds and light feeds, kerosene or light emulsion coolant; excellent surface finish and tapping behaviour.
Can ZA-8 be welded?
Not a weldable structural alloy — narrow freezing range and Zn volatility; repair only by zinc-based soldering/brazing or metal-filled epoxy, joins normally by cast-in features, screws or adhesives.
Can ZA-8 be formed, bent or molded?
Hot-chamber die castable at ~430–450 °C with thin walls (0.8 mm) and long die life; also sand, permanent-mould and graphite-mould gravity cast — avoid overheating melt and control Fe pickup.
What surface finishes work on ZA-8?
Not anodizable; chromate/trivalent passivation, Cu-Ni-Cr or electroless-Ni plating and powder/wet paint over phosphate all work well, and the surface buffs to a bright polish.
ZA-8 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Al | 8 – 8.8 | 8.4 |
| Cu | 0.8 – 1.3 | 1 |
| Mg | 0.02 – 0.03 | 0.02 |
| Femax; 0.035 max for ingot | ≤ 0.08 | — |
| Pbimpurity max — intergranular corrosion control | ≤ 0.01 | — |
| Cdimpurity max | ≤ 0.01 | — |
| Snimpurity max | ≤ 0 | — |
| Znbalance, 99.99% Zn base | balance | — |
ZA-8 Sand Cast — frequently asked
What is ZA-8 Sand Cast used for?
ZA-8 Sand Cast is typically used for bearings, bushings and industrial gears. In short: higher-strength ZA die-cast.
What is the yield strength of ZA-8 Sand Cast?
ZA-8 Sand Cast has a typical yield strength of 200 MPa (29 ksi) and a tensile strength of 250 MPa (36.3 ksi) — stronger than 57% of zinc alloy grades. Strength varies by condition: see the 5 listed tempers.
Is ZA-8 Sand Cast easy to machine?
Yes — machinability is rated very good (82/100, better than 86% of zinc alloy grades). Machines very easily with sharp positive-rake carbide or HSS tools, high speeds and light feeds, kerosene or light emulsion coolant; excellent surface finish and tapping behaviour.
Can ZA-8 Sand Cast be welded?
Not readily — weldability is rated poor (20/100). Not a weldable structural alloy — narrow freezing range and Zn volatility; repair only by zinc-based soldering/brazing or metal-filled epoxy, joins normally by cast-in features, screws or adhesives.
What surface finishes work on ZA-8 Sand Cast?
Not anodizable; chromate/trivalent passivation, Cu-Ni-Cr or electroless-Ni plating and powder/wet paint over phosphate all work well, and the surface buffs to a bright polish.
Can ZA-8 Sand Cast be formed, bent or molded?
Hot-chamber die castable at ~430–450 °C with thin walls (0.8 mm) and long die life; also sand, permanent-mould and graphite-mould gravity cast — avoid overheating melt and control Fe pickup.
What is the maximum service temperature of ZA-8 Sand Cast?
ZA-8 Sand Cast is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ZA-8 As Cast and ZA-8-DIE?
As Cast is the default condition — default commercial condition: thin-wall hot-chamber die castings with the highest strength and hardness of the ZA-8 forms. DIE: hot-chamber pressure die cast ZA-8 (ASTM B86 / UNS Z35636): fine chill-cast structure giving the highest strength and hardness of the as-cast ZA-8 conditions. Yield strength is 290 MPa in As Cast versus 290 MPa in DIE.
Can FabDigit make parts in ZA-8 Sand Cast?
Yes — ZA-8 Sand Cast is available for CNC machining with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM B86 — Zinc and Zinc-Aluminum (ZA) Alloy Foundry and Die Castings — ASTM International (2018)
- ASTM B669 — Zinc-Aluminum Alloys in Ingot Form for Foundry and Die Castings — ASTM International (2019)
- ASTM B240 — Zinc and Zinc-Aluminum Alloys in Ingot Form for Castings — ASTM International (2016)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys (Zinc and Zinc Alloys) — ASM International (1990)
- ZA-8 Zinc Alloy Casting Data / Zinc Casting Design Guide — ILZRO / International Zinc Association (2011)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.