ER4043 (commonly referred to as AISi5) is a 5% silicon aluminum filler metal that is available in spools or cut lengths for MIG or TIG processes. This alloy is recommended for welding 3003, 3004, 5052, 6061, 6063 and casting alloys 43, 355, 356 and 214. Washington Alloy 4043 has a melting range of 1065- 1170°F and a density of .097 Ibs/cu.in. The post-anodizing color tint is gray. Tensile strength average is 29,000 psi.