Tribological behavior of novel Al–La–Mg–Mn alloy fabricated by laser powder bed fusion

Al–(La, Ce) alloys have been extensively fabricated by laser powder bed fusion, exhibiting outstanding mechanical properties. Owing to the critical role of wear resistance, this work investigated the room-temperature wear behavior with varied normal load for novel Al–La–Mg–Mn alloy fabricated by LPBF and spheroidized heat treatment, where the as-printed alloy achieved better wear resistance than spheroidized alloy. For as-printed alloy, the delamination and oxidation wear mechanisms dominated the whole sliding process with normal load of 10 N. The network intermetallic and tribo-induced nanograined structure cooperativity endowed the as-printed alloy with excellent wear resistance. When the normal load increase to 20 N, the higher frictional stress induced higher wear rate, resulting in higher volume fraction debris formed. The frictional heat and increased load promote the debris densification into glaze layer, protecting the surface against serve wear damage. Further increase the normal load to 30 N, similar wear behaviors were found, only causing the slight increase in wear rate. Consequently, the formation of network intermetallic, tribo-induced nanograined structure and smooth glaze layer is critical for enhancing the wear resistance of the LPBF-fabricated Al–La–Mg–Mn alloy. These findings provide the first insight into the tribological behavior of the LPBF Al–(La, Ce) alloys, promoting its application.