Several types of Zamak exist. The three types of Zamak alloys most currently used in die-casting are Zamak 12, Zamak 13 e Zamak 15.
These types differ by higher or lower copper content (0 to 3%). Copper is used to provide more hardness and resistance to Zamak alloys.
ZAMAK 12
Among Zamak alloys, ZAMAK 12 offers the best hardness and traction resistance qualities.
ZAMAK 13
Among other Zamak alloys, ZAMA 13 stands out for its great impact resistance behavior and for its higher dimensional stability with aging. Very good corrosion resistance when subject to severe environmental conditions.
ZAMAK 15
ZAMAK 15 combines good impact resistance and dimensional stability over time close to those that can be attained with Zamak 13 alloy. Its corrosion resistance is also good, even in critical environmental conditions.
Chemical Composition (%) | ZAMAK 12 ZL2 – ZnAl4Cu3 |
ZAMAK 13 ZL3 – ZnAl4 |
ZAMAK 15 ZL5 – ZnAl4Cu1 |
---|---|---|---|
Al | 3.8 – 4.2 | 3.8 – 4.2 | 3.8 – 4.2 |
Cu | 2.7 – 3.3 | ≤ 0,03 | 0,7 – 1,1 |
Mg | 0,035 – 0,060 | 0,035 – 0,060 | 0,035 – 0,060 |
Pb | ≤ 0,0030 | ≤ 0,0030 | ≤ 0,0030 |
Fe | ≤ 0,0200 | ≤ 0,0200 | ≤ 0,0200 |
Cd | ≤ 0,0030 | ≤ 0,0030 | ≤ 0,0030 |
Sn | ≤ 0,0010 | ≤ 0,0010 | ≤ 0,0010 |
Si | ≤ 0,0200 | ≤ 0,0200 | ≤ 0,0200 |
Ni | ≤ 0,0010 | ≤ 0,0010 | ≤ 0,0010 |
Physical Properties | ZAMAK 12 ZL2 – ZnAl4Cu3 |
ZAMAK 13 ZL3 – ZnAl4 |
ZAMAK 15 ZL5 – ZnAl4Cu1 |
---|---|---|---|
Specific weigh Kg/dm³ | 6,70 | 6,60 | 6,65 |
Melting point lowest °C highest °C |
379 389 |
380 386 |
380 386 |
Specific heat cal/g/°C | 0,102 | 0,098 | 0,105 |
Thermal conductivity at 20°C Cal/sec/cm/°C | 0,25 | 0,27 | 0,26 |
Resistivity μ Ω cm Ω mm²/m |
6,75 0,0675 |
6,40 0,0640 |
6,55 0,0655 |
Electrical conductivity at 20°C 1/ μ Ω cm S m/mm² |
0,146 14,6 |
0,157 15,7 |
0,153 15,3 |
Elastic modulus E Kg/mm² | 10.000 | 10.000 | 10.000 |
Coefficient of thermal expansion x 10¯⁶/°C | 27,7 | 27,4 | 27,4 |
Linear shrinkage % | 1,25 | 1,17 | 1,17 |
Maximum melting temperature °C | 480 | 480 | 480 |
Optimal range of pressure casting °C | 400 ÷ 440 | 400 ÷ 440 | 400 ÷ 440 |
Temperature of molds under pressure °C | 200 | 200 | 200 |
Mechanical Specifications | ZAMAK 12 ZL2 – ZnAl4Cu3 |
ZAMAK 13 ZL3 – ZnAl4 |
ZAMAK 15 ZL5 – ZnAl4Cu1 |
---|---|---|---|
Breaking load Kg/mm₂ | 30 ÷ 33 | 25 ÷ 28 | 28 ÷ 31 |
Elongation % | 2 | 1,5 | 2 |
Brinell hardness Kg/mm² | 85 ÷ 100 | 70 ÷ 85 | 80 ÷ 90 |
Resilience Kgm/mm² | 1,5 | 2 | 1,5 |