... roll weldingl Special steel horn,long life(1 million times)l For different or similar kinds metal(such as copper + ... phosphor copper, brass, redcopper, bronze, nickel, gold high-conductivity metal weldingSolid solder joint, solder joint resistance is small, no traces ... , safe, easy to operate.Welding range:Battery pole piece of metal welding processes: aluminum + nickel, nickel + copper, multi-layer ...