Altering the Tribological Properties of Laser Powder Bed Fusion Materials through Various Methods: A Review

Additive Manufacturing has gained prominence in research due to its cost-effectiveness and design flexibility. However, the connection between tribology and Laser Powder Bed Fusion remains inadequately investigated despite its potential. This study examines various direct manufacturing methods (i.e., without post-processing), in order to identify the most effective technique for modifying tribological properties. The wear rate and coefficient of friction are influenced by densification, which is affected by the formation of melt pools and keyholes in the microstructure. Notably, there is conflicting evidence on the most influential processing parameter for wear. Some studies suggest that laser power holds the greatest significance, while others propose that scan angle has a more pronounced effect on wear behaviour. Additionally, texturing emerges as another tribology manipulation method, enabling the entrapment of lubricants and debris within the system. The study also explores the relationship between microhardness, volumetric energy density, wear, and friction.