Copper and brass have good stamping performance. They have high compressive strength, good ductility and durability. Bronze, on the other hand, is of lower performance in stamping process because it has strong cold work hardening. Copper is suitable for both cold stamping and hot stamping while brass and bronze is mostly only suitable for cold stamping. Arc welding is the best welding method for copper and copper alloy, which can protect the molten pool from oxidation and gas. Gas welding, manual arc welding, etc. can also be applied, but appropriate process measures must be taken. Since the electric resistance of copper is small, electric resistance welding is not suitable for it.