Zamak-5 vs Zamak-3 Zinc Alloys: Copper Strengthening in Housing Components
Engineering Overview: Metallurgical comparison of Zamak-3 and Zamak-5 die-cast zinc alloys, evaluating tensile strength, hardness, and dimensional creep stability.
Technical & Engineering Specifications
| Hardness | 82 HB (Zamak-3) vs 91 HB (Zamak-5) |
|---|---|
| Application | Residential Escutcheons, Strike Plates, Knob Housings |
| Alloy Grades | Zamak-3 (ZL0400) vs Zamak-5 (ZL0410) |
| Copper Content | 0.0% (Zamak-3) vs 0.7-1.1% (Zamak-5) |
| Tensile Strength | 280 MPa (Zamak-3) vs 330 MPa (Zamak-5) |
Zinc Die-Casting Alloy Selection
In economy residential locksets, zinc alloys are specified for outer escutcheon trim and non-critical housing shells.
Metallurgical Distinction
- Zamak-3: Standard baseline alloy (4% Al, balance Zn). Excellent fluidity and impact ductility.
- Zamak-5: Incorporates 1.0% Copper (Cu) into the zinc-aluminum matrix. The copper additions increase tensile strength by 15% (330 MPa vs 280 MPa) and Brinell hardness (91 HB vs 82 HB), offering superior thread retention and dimensional stability under creep loads.
Frequently Asked Engineering & Selection Questions
Q1: Why is Zamak-5 stronger than Zamak-3?
Zamak-5 contains 1% copper, which increases tensile strength by 15% and hardness to 91 HB, improving thread stripping resistance.