What is the material composition of a vehicle's axle?

A general composition will do, but if anyone knows the composition of a 2003 Honda Accord LX 3.0L front axle that would be best. I am doing a case study project in my material science class. I assume it is a type of steel, but don't know what kind. I also assume it is heat treated. If anyone knows the treatment process it goes through that would also help.

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