A Design Study in Aluminum Castings
- GM Cylinder Block
Aluminum
Alloy 242 T77
Alloy
242 is a 4Cu-2Ni-2.5 Mg alloy. The T77 heat treatment is an
solution- annealed alloy with a 650F aging.
Alloy
242 is used extensively for applications where strength and hardness
at high temperatures are required.
Typical
applications include: heavy-duty pistons motorcycle, diesel and
aircraft pistons; and aircraft generator housings.
Not
suitable for complex, heavy section parts (blocks/heads) because
of low fluidity and misruns.
The
Alloy 242 has good ductility, hardness, fatigue strength, and machinability, but the alloy
fails to meet the requirements for tensile strength, yield strength,
pressure tightness, and castability/fluidity.
