... welding wire ER70s-6 welding carbon steel,500MPa high strength steels,welding in cars,building,bridges copper coated co2 gas shielded welding wire AWS ER70s-61) welding wire ER70S-6 ... ,5kg,15kg,18kg,20kg chemical composition of welding wire(%)CMnSiPSCrNiCu0.06~0.151.40~1.850. ... wire rust.Before welding please clean out the oil,rust,water etc from the work parts co2 gas shielded welding wire AWS ER70s-6 ...