Zinc Alloy

Basic Properties

Zinc alloy (ZA series, Zamak 3 / ZA-3 and ZA-5, ZA-8, ZA-12, ZA-27) is a low-cost, high-precision die-casting and machining alloy with excellent dimensional stability.

• Low melting point (about 385 °C) and excellent castability: thin walls, fine detail and sharp edges are easy to reproduce.
• Very good machinability: free-cutting chips, high surface quality straight from the tool, low tool wear.
• Good strength and dimensional stability: ZA-3 holds tolerances well and takes plating and painting without distortion.
• Natural corrosion resistance: a protective oxide / chromate layer forms, further improved by plating or coating.
• High density (about 6.6 g/cm³): gives a solid feel to hardware, locks and decorative parts.
• Drawbacks: creep strength drops above about 100 °C; intergranular corrosion can occur in steam or humid service if impurity levels (Pb, Sn, Cd) are not controlled.

Common Surface Finishes for Zinc Alloy

1. Chromate conversion coating: clear, blue or yellow passivation for indoor corrosion protection.
2. Zinc-nickel or copper-nickel-chrome plating: bright decorative and wear-resistant surfaces.
3. Powder coating and e-coating: durable colour finishes for architectural and automotive parts.
4. Vibratory polishing and tumbling: removes parting lines and burrs before plating.
5. Laser marking and engraving: permanent logos and part numbers on hardware.

Main Applications

• Hardware and builders’ fittings: locks, hinges, handles, door and window furniture.
• Plumbing and valves: bodies, cartridges, fittings and irrigation components.
• Electrical: conduit fittings, connectors, junction boxes and terminal blocks.
• Automotive: brackets, trim, instrument parts and small structural castings.
• Fasteners, gears, decorative and instrument components where cost and precision both matter.

Material parameters