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Pressure Die Casting Alloy ZL3

This zinc die casting alloy conforms to EN 1774 1997

Chemical Composition

  %   %   %
Aluminium 3.8-4.2 Magnesium 0.035-0.06 Zinc Remainder
Iron 0.020 Copper 0.03 max  Lead  0.003
 Cadmium  0.003  Tin  0.00.1 max  Nickel  0.001 max
 Sodium  0.02        


Mechanical Properties of Zinc ZL3



Tensile Strength at 20°C (N/mm2)

283 - 241

Elongation at 20°C (% in 2 inches)

10 - 16%

Brinell Hardness

82 - 87

Impact Strength at 20°C (J)


Strength at elevated temperatures

The advantage of a comparatively low melting point which allows zinc die casting to such close dimensional limits entails the disadvantages that zinc alloys cannot be used at elevated temperatures.

In cases where the temperature is likely to be maintained for considerable periods of time, the maximum temperature recommended is 150°C for unstressed parts and 100°C when light stresses are involved. Where a zinc die casting is to operate under continual stress, and changes in dimensions are critical, creep data should be consulted.

Physical Properties of Zinc ZL3



Coefficient of Thermal Expansion (per °C @ 20-100°C)


Thermal conductivity (cal/cm2/cm/°C @ 25°C)


Electrical conductivity (% copper standard @ 20°C)


Density (g/cm3)


Freezing range (°C) approx.



This zinc alloy has excellent machining characteristics which means fast, efficient machining and long tool life. Therefore, unlike its competing materials, it is the ideal alloy for a casting requiring substantial or difficult machining.


A die casting in this zinc alloy possesses good resistance to corrosion. In general, its behaviour may be expected to resemble that of unalloyed zinc, and a zinc die casting may be used with confidence wherever the latter is known to be satisfactory.


A process for anodising zinc and zinc alloy die castings has been developed and is reported to give excellent resistance to salt water and good resistance to abrasion. The finish is available only in matt light green, grey and brownish tints. The treatment is covered by U.S. Government specification MIL-A-81801.


ZL3 is a general purpose alloy which can be used for a variety of applications, on a hot chamber pressure die casting machine. Its mechanical and physical properties make it ideal for use in die castings for the engineering and automotive industry, household equipment and utensils, office equipment, builder's hardware, locks, toys, giftware, etc. It is easily machined, buffed, polished, lacquered and electro-plated for decorative or functional purposes.

Notes for Designers of Non-Ferrous Castings


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