What Welding Does to Aluminum

This is an issue that architects, engineers and contractors need to look out for. Welding aluminum may create issues that do not get much attention for steel: the effect of the welds on the strength of the base metal. Welding significantly reduces the strength of the aluminum base metal. Reason being, the heat created by welding reduces the yield and ultimate strength of aluminum alloys that get their strength from various heat-temper treatments. Reductions in strength may exceed 50-60%. In a nutshell, if you weld aluminum improperly, you risk significantly reducing the strength of the welded member. Building officials and inspectors are aware of this and you run the risk of them red tagging your project. Therefore, structural calculations by a registered Professional Engineer or a Product Approval are a must.