6 Metals in foil or powder form for 3d printers; common metals in powder form; iron and steel; alloys of common metal; castings, foils, powder, and rolled, drawn or extruded semi-finished articles of nickel or its alloys; castings, foils, powder, and rolled, drawn or extruded semi-finished articles of cobalt or its alloys; castings, foils, powder, and rolled, drawn or extruded semi-finished articles of titanium or its alloys; castings, foils, powder, and rolled, drawn or extruded semi-finished articles of copper or its alloys