... strength steels,welding in cars,building,bridges copper coated co2 welding wire AWS ER70s-61) welding wire ER70S-6 have excellent mechanical performance ... D300mm K300mm 1kg,5kg,15kg,18kg,20kg chemical composition of welding wire(%)CMnSiPSCrNiCu0.06~0.151.40~1.850.80~1 ... wire rust.Before welding please clean out the oil,rust,water etc from the work parts co2 welding wire AWS ER70s-6 of copper ...