Zamak 7

Zamak 7 (ASTM AG40B), or Zinc Alloy 7, is a modification of Zamak 3. It is a high-purity alloy containing lower magnesium content and has a tighter impurities specification. This results in improved casting fluidity, ductility and surface finish.

Applications ideal for Zamak 7

Zamak 7 is mostly used for special hardware applications, or when castings require extra formability during subsequent assembly operations such as crimping or staking. Its higher fluidity also allows thinner walls to be cast:

  • Higher fluidity is sometimes desirable especially on components with intricate detail, however it does present special casting considerations
  • In order to avoid excessive flashing along the tool parting lines, good die fit and close control of casting process paraMetres is necessary
  • The high ductility exhibited by this alloy also has an impact on processing, but mainly in secondary operations for flash removal and trimming
  • Zamak 7 exhibits excellent damping capacity and vibration attenuation in comparison with Aluminium die casting alloys

Mechanical Properties

Material Alloy Tensile Strength   Elongation   Hardness   Impact Strength   Young's Modulus   Yield Strength (0.2%)   Fatigue Strength   Creep Limit   Process
MPa
% in 50mm
Brinell (HB)
J
Gpa
MPa
Mpa
Mpa
Zinc
283
13
80
58
-
221
-
-

Physical Properties

Material Alloy Density   Melting Point (Average +/- 50)   Coefficient of Thermal Expansion   Thermal Conductivity   Electrical Conductivity   Process
g/cm3
°C
µm/m°K
W / m K
% IACS
Zinc
6.60
384
27.4
113
27.0

Composition

Zinc
% Zamak 7
Aluminum 3.5-4.3
Copper 0.25
Magnesium 0.005-0.02
Iron (max) 0.075
Lead (max) 0.003
Cadmium (max) 0.002
Tin (max) 0.001
Nickel (max)
Zinc Bal.
Manganese
Silicon
Other-Metallic
Titanium -
Chromium -
RoHS Compliant

 

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Last updated 03.22.2021