Materials: Sheet in aluminum, mild steel, 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 ... Use: With good strength, wear resistance and nice looking, expanded sheet metal mainly serves to construction of railway, roads, buildings; also protection ...