Zamak 3 (ASTM AG40A): Standard Zinc Die Casting Alloy

ASTM B86 · Published: 2026-06-01 · Updated: 2026-06-02

Quick Reference

Zamak 3 (ASTM AG40A) is the de facto standard zinc die casting alloy, containing approximately 4% Al, 0.04% Mg, and ≤0.25% Cu. It provides the optimum balance of castability, dimensional stability, and mechanical properties at the lowest cost...

Zamak 3 (ASTM AG40A) is the de facto standard zinc die casting alloy, containing approximately 4% Al, 0.04% Mg, and ≤0.25% Cu. It provides the optimum balance of castability, dimensional stability, and mechanical properties at the lowest cost among zinc alloys. Hot-chamber die casting at 380-430°C enables the highest production rates of any metal casting process—cycle times of 1-2 seconds for small components. Excellent for thin-wall (0.5 mm minimum), complex net-shape parts requiring tight tolerances (±0.05 mm achievable). Used for automotive door lock housings, zipper components, plumbing fittings, and electronic connector bodies.

Quick Facts

CategoryZinc Alloy
StandardASTM B86
Density6.60 g/cm³
Yield StrengthN/A (brittle)
Tensile Strength283 MPa (41 ksi)

Global Equivalents & Cross-Reference

Alternative Standard / GradeAction
EN ZnAl4 Compare
ZP0400 Compare
JIS ZDC2 Compare
ISO ZnAl4Cu1 Compare

🧮 Material Weight Calculator

Calculate the weight based on this material's density: 6.60 g/cm³

Frequently Asked Questions

What is the difference between Zamak 3 and Zamak 5?

Zamak 5 adds approximately 1% copper to improve tensile strength (328 vs 283 MPa) and hardness at a small cost in ductility (7% vs 10% elongation). Zamak 3 is preferred for most applications due to better dimensional stability and castability.

References & International Standards

  • ASTM International. Standard Specifications for Steel & Metal Alloys. astm.org
  • International Organization for Standardization (ISO). Metallic Materials — Cross-Reference Database. iso.org
  • American Iron and Steel Institute (AISI). Steel Grade Designations & Equivalents. steel.org
  • European Committee for Standardization (CEN). EN Steel Standards & Numbering System. cencenelec.eu