... steel,500MPa high strength steels,welding in cars,building,bridges copper coated co2 welding wire AWS ER70s-61) welding wire ER70S ... D200mmD270mm D300mm K300mm 1kg,5kg,15kg,18kg,20kg chemical composition of welding wire(%)CMnSiPSCrNiCu0.06~0.151.40~1.850.80 ... from the work parts co2 welding wire AWS ER70s-6 of copper coating factory