If you cut something in half, do you get two parts or two pieces? Do they convey different meanings? This is in the context of a mechanical part physically cut in two.
1 Answer
In the context of a mechanical assembly, I would understand 'part' to refer to a component or subassembly which might have been dismounted from the whole, while 'piece' would be an arbitrary fragment, e.g. that resulting from a straight cut or break.