ZL8 is a hot chamber pressure die casting alloy
ZL8 conforms to EN 1774 1997 Ingot Specification, was developed to meet specific applications and is one of the family of versatile high-grade alloys we manufacture in. ZL8 is a direct replacement for ZA8 and can also be used to make sand and permanent mould castings.
Application
ZL8 is designed to extend the application range of Zinc alloy die castings. In the past Zinc alloys were considered unsuitable for applications where moderate stress was anticipated at elevated temperatures. ZL8 offers the best creep resistance of all hot chamber diecasting alloys and it should be specified for structural or stressed applications for which other Zinc alloys would be unsuitable. Although it is the strongest of the hot chamber alloys, it still possesses all the properties associated with Zinc diecasting alloys. The combination of high strength, excellent dimensional stability, good surface finish and definition make it ideal for visible stressed parts which are subject to elevated temperature during service. The increased levels of Aluminium have no significant effects on the finishing of castings made from this alloy. Finishes suitable for traditional Zinc pressure die casting alloys can be applied to castings made from ZL8 alloys with excellent results. Typical applications for this alloy are under bonnet automotive parts, stressed parts for hazardous or mining environments, stressed electrical or computer parts.
This specification has been taken from EN 1774 – Zinc and Zinc Alloys – Alloys for Foundry Purposes – Ingot and Liquid.
The Noranda Research Centre, Quebec, Canada, developed the ZL8 alloy and carried out the detailed characterization of the material properties pertaining to this alloy.
MIN | MAX | |
Aluminimum | 8.2% | 8.8% |
Copper | 0.9% | 1.3 |
Magnesium | 0.02% | 0.03% |
Zinc | REMAINDER |
Iron | - | 0.035% |
Lead | - | 0.005% |
Cadmium | - | 0.005% |
Tin | - | 0.002% |
Nickel | - | 0.001% |
Silicon | - | 0.035% |
Pressure Die Casting | ||
Casting Temperature | °C | 415-435 |
Freezing Range | °C | 375-404 |
Specific Heat | J/GK | 0.4354 |
- | (0.104) | |
Solidification
Shrinkage |
Cm/m | 1.10 |
(in/ft) | (0.132) | |
Casting Shrinkage | Mm/mm | 0.007 |
(in/in) | (0.007) | |
Thermal Conductivity at 18 °c | W/m°C | 114.7 |
BTU/FT/hrFT²/P | 66.3 | |
Thermal Expansion Linear
per °c |
- | 23.3X10₆ |
Pressure Diecasting | ||
Electrical Conductivity
At 20°C |
%age
IACS |
27.7 |
Specific Gravity | - | 6.3 |
Density | Kg/m₃ | 6300 |
(ib/in₃) | (0.227) | |
Tensile Strength at 20°c | N/mm² | 374 |
(ib/in²) | (54200) | |
Elongation at 20°C | %in 2in | 6-10% |
Impact strength at 20°C
(unnotched samples) |
J
(ft.obf) |
42
(31) |
Hardness | BHN | 103 |
Figures relate to material in casting form. Properties vary for different processes. Further data available on request.