Is there a way to accomplish this?

I would like to set a value in the assembly equations (For example 1=mild steel, 2=Stainless).

This way I can suppress or unsuppress certain parts (1= unsuppress steel parts and suppress stainless parts).

But i also have one weldment in this assembly. Can I control the weldments material by the assembly equations? Or do I have to copy this part also?

Thanks in advance