How can I determine what type of iron

Camshafts are normally made from alloy cast iron with the cam lobes hardened by introducing chills during the casting process.
The cheapest method of obtaining the properties of the Chinese material is to cut a section off and examine the microstructure then do a hardness test.

I don't know what the standard practice is, but I would get the shaft Case Hardened. The center needs to stay ductile so some degree so it dosen't snap. The surface of the lobes needs to be hard so it dosen't wear. Case Hardening is done when the item is placed in a box of carbon or charcole and put in a oven for a long time. Depending on time allowed and heat, the carbon soaks into the outside layer of metal making it harder. Maybe only 0.1mm, not sure. If it is a low grade steel, hardening it with just heat will not be effective. One grade of case hardening steel I have used is EN36a I think. If the material can be hardened with just heat (steel alloy), the surface of the lobes can be heat treated with a flame, called flame hardening.