The casting of Aluminum Alloys comprises the largest part of O’Fallon Casting’s business. Most common are aluminum-silicon alloys 356 / A356 / C355 / A357 / F357. These alloys have excellent castability, weldability, pressure tightness and corrosion resistance. They are heat treatable and can be provided in various combinations of physical properties (typical properties are show below).
The most frequently cast aluminum alloys are 356 and its higher purity version, A356. These are good general purpose alloys and because they are in wide use also makes 356 & A356 advantageous in terms of cost and delivery.
A357 alloy contains a larger magnesium content than does A356 so can be heat treated to higher strength levels. A357 contains a very small amount of beryllium so its use does present an inherent safety hazard.
F357 is a beryllium free variant of A357 though less strong, is a common substitute for that alloy.
C355 alloy contains a larger presence of copper, making it stronger but less ductile than A356. At elevated temperatures, C355 maintains its strength better than other aluminum-silicon alloys.
For more about our Aluminum Alloys and chart on their comparative properties, see below: