Zamak 7 is a modification of Zamak 3 in which lower magnesium content is specified to improve fluidity. To avoid problems with intergranular corrosion, lower levels of impurities are required and a small amount of nickel is specified. Zamak 7 also has slightly better ductility than Zamak 3 with other properties remining relatively equal. It is a popular choice for those special cases where the die caster is making thin walled components requiring a good surface finish. However, research has shown that metal and die termperatures have a greater effect than changing alloys. Close attention to control of the die casting process is important so as to eliminate defects and achieve a consistent quality.
Typical Mechanical Properties
|UTS: ksi (MPa)||Yield Strength: ksi (MPa)||Elongation: %||Hardness: Brinell||Modulus of Elasticity: psi x 10^6|
|41 (283)||32 (221)||13||80||12.4|
Typical Physical Properties
|Density: lb/in^3 (g/cc)||Melt Range: deg F (deg C)||Electrical Conduct: %IACS||Specific Heat: BTU/lb/deg F||Die Shrinkage: in/in|
|0.240 (6.6)||718-728 (381-387)||27||0.10||0.007|
|Ingot (ASTM B240)||3.9-4.3||.010-.020||.10 max||0.035 max||.003 max||.002 max||.001 max||.005-.020||balance|
|Die Cast (ASTM B86)||3.7-4.3||.005-.020||.1 max||.05 max||.003 max||.002 max||.001 max||.005-.020||balance|
For additional properties of Zamak 7 and other zinc die casting alloys, please visit our technical library.