Sliding wear and debris evolution in LPBFed ceramic-reinforced steel composites under variable loads and temperatures
H.S. Maurya, Rahul Kumar, Sudheer Kumar, Marek Tarraste, Abrar Hussain, Ramin Rahmani, Kristjan Juhani, Fjodor Sergejev, Konda Gokuldoss Prashanth
Abstract
In this study, TiC-ferritic steel-based green composites were fabricated via Laser Powder Bed Fusion (LPBF) using a rescanning strategy to develop a complex hierarchical microstructure comprising (sub)grains, fine precipitates, and a bimodal TiC morphology. Sliding wear tests under varying loads and temperatures were conducted to investigate friction and wear behavior. Results revealed a higher coefficient of friction (COF) range of 0.59-0.52 at 25 N, which decreased significantly to 0.24-0.3 at 75 N under both room temperature (RT) and elevated temperatures (ET). Correspondingly, wear rates dropped by at least an order of magnitude. At lower sliding load (25 N), abrasive wear dominated due to unstable debris dynamics, resulting in higher friction and wear loss. At higher loads (50-75 N), fatigue-driven mechanisms, including adhesion and delamination, became prominent. Under ET, tribochemical interactions promoted partial debris compaction and formation of a wear-resistant mechanically modified layer. High-load ET conditions induced cyclic self-organization of the tribo-surface, resulting in the formation of a protective tribolayer. The load and temperature-dependent wear mechanisms are discussed in detail in support with SEM, EDS, and 3D profilometry analysis .