Influence of heat treatment on wear behaviour of WE43 magnesium alloy manufactured by LPBF

This study investigates the dry sliding wear behaviour of WE43 magnesium alloy fabricated by Laser Powder Bed Fusion (LPBF) in the as-built condition and after T5 and T6 heat treatments. Microhardness measurements and SEM observations of the microstructure and worn surfaces were used to interpret wear trends under loads of 2 and 20 N and sliding speeds of 0.05 and 0.1 m/s. The as-built condition showed the lowest wear rates in most test conditions, whereas T5 exhibited higher wear despite the highest hardness (≈98 HV), and T6 showed severe material removal under the most demanding condition (20 N, 0.1 m/s), consistent with extensive cracking/delamination features on the wear track. Overall, wear rate increased with load and generally decreased with sliding speed, although deviations occurred when delamination became dominant. Compared with literature data on conventionally processed WE-series alloys (noting differences in alloy grade and test conditions), the LPBF as-built condition exhibited markedly lower wear rates, highlighting the tribological advantage of the refined LPBF microstructure and the need to tailor post-heat treatments to preserve it.