Difficulties in Aluminum Alloy Processing and Their Solutions - The Softening Problem

• Challenge: The strength of aluminum alloys usually relies on deformation strengthening or solution aging strengthening. However, the heat generated during the welding process can cause these strengthening effects to disappear, resulting in a decrease in the strength at the joint and the heat-affected zone. Softening is particularly prominent in high-strength aluminum alloys, such as the 2XXX series and 7XXX series. 

• Solution: Select the base material and welding wire reasonably to ensure their composition and performance are compatible, avoiding significant differences between the weld and the base material to reduce the risk of softening; Adjust the welding current, speed, and preheating treatment before welding to reduce the temperature and range of the heat affected zone, effectively preventing overheating; Some aluminum alloys can undergo post-weld heat treatment (such as aging treatment) to restore or enhance the strength of the weld and the heat affected zone, and select appropriate heat treatment processes based on the characteristics of different aluminum alloys.