Effect of deposition path strategies on residual stress distribution in CMT+P WAAM of 205C aluminum alloy

Residual stress is a persistent barrier to the structural reliability of aluminum components produced by Wire Arc Additive Manufacturing (WAAM). This study evaluates the influence of deposition path strategies on residual stress distribution in 205C aluminum alloy using the Cold Metal Transfer plus Pulse (CMT+P) process. Two contrasting deposition paths— linear reciprocating (Z-path) and spiral closed-loop (O-path)—were compared under identical thermal and geometric conditions. X-ray radiography and ultrasonic testing were employed to assess internal defects and residual stress fields along both transverse (TD) and welding (WD) directions. Results show that the Z-path promotes more uniform stress distributions with lower variance, whereas the O-path leads to localized stress accumulation due to thermal overlap. Two-dimensional stress maps and statistical metrics confirmed significant path-dependent variations in stress orientation and concentration. The results underscore the role of deposition path in governing thermo-mechanical behavior and offer a basis for residual stress optimization in WAAM-fabricated aluminum components.