... stainless steel, Al-Mg alloy, copper or nickel. Process: Punched into holes of diamo Materials: Sheet in aluminum, mild steel ... , stainless steel, Al-Mg alloy, copper or nickel. Process: Punched into holes of diamond shape, square, round, triangle, scale hole ... With good strength, wear resistance and nice looking, expanded sheet metal mainly serves to construction of railway, roads, buildings; also ...