2019 Volume 60 Issue 1 Pages 156-164
This study evaluates the tribological behavior of borided AISI 316L steel. The treatment time was set to 2, 4, and 6 h at temperatures of 850, 900, and 950°C for each time duration. The morphology and microstructure of the boride layers were analyzed by scanning electron microscopy (SEM) and X ray diffraction (XRD), respectively. The mechanical properties were evaluated by an instrumented nanoindentation test. The tribological behaviors of the layers were evaluated using a sand/rubber apparatus following the ASTM G-65 standard. The friction coefficient of the boride layers was estimated by means of the tribological pin-on-disk test. The results show that the experimental parameters had a clear influence on the thickness of the boride layers and on their mechanical properties. The volume loss was established in the range of 0.0741 ± 0.011 µg to 1.6148 ± 0.150 µg. Wear mechanisms such as adhesion and micro-fatigue were mainly observed in the samples exposed for 6 h at 950°C. Finally, the friction coefficient was reduced from 0.7 for the as-received material down to 0.29 for the borided samples. The wear mechanisms were discussed as a function of the scanning electron microscopy observations. It is possible to conclude that single-phase layers of Fe2B are more apt to face wear than the FeB/Fe2B biphasic layers.