Tribological performance of additive-manufactured aluminum alloy—effect of post-weld cold deformation

Aluminum alloys are widely used in various automotive parts because of their high strength-to-weight ratio. However, their tribology properties, such as wear rate, are relatively high, resulting in a shorter life span than expected. Reconstructing the worn area using welding-based additive manufacturing (AM), such as wire arc AM, offers many advantages. However, heat may decrease the strength and hardness of the deposited material. This study intends to investigate the tribology properties of additive-manufactured aluminum alloy and their effects on mechanical deformation via cold forging. In this study, a reciprocating ball-on-flat test based on ASTM G133 is utilized. The additive-manufactured aluminum alloy ER5356 is studied based on three parameters, i.e. forged/unforged condition, speed, and load. In conclusion, cold forging improves the properties of the deposited material. Optimization using the Taguchi method and analysis of variance verifies that cold forging condition is the most significant parameter for the coefficient of friction and wear rate pattern. The SEM observation seems to agree with the wear pattern.