Ironability of a three-layered polymer coated steel: Part 1: Experimental investigation

Food and beverage containers are common in Western society, with over one billion beverage containers produced annually in the United States alone. One of the environmental concerns associated with the manufacture of these products is the production of volatile organic compounds during the coating of the can interior with a protective polymer. This issue can be resolved by using pre-laminated steels as a base stock, so long as the polymer coating is robust and can survive the can making operation. Recognizing that ironing is the most demanding metal forming operation in can making, a series of formability tests were conducted on novel laminated polymer-coated steel specimens using an ironing simulator. It was found that the laminate-coated steels could display good ironability with tin-free steel substrates. The surface quality was evaluated and related to process parameters, of which the ironing angle was determined as the most important factor. With proper tooling and layer design, polymer laminate base stocks have been demonstrated to be suitable for drawn and ironed containers.