Anti-tribocorrosion resistance of NiTi-CeO2 alloys fabricated by laser powder bed fusion

Alloying treatment is a common method to enhance metallic properties, but its application in laser powder bed fusion (LPBF) is still very limited, especially for LPBF-NiTi alloys. Rare earth elements as common alloying el-ements have been used in the modification of different LPBF-metals. In the case of LPBF-NiTi alloy, the application of rare earth alloying is only for mechanical functionality, but its influence on anti-tribocorrosion resistance is always neglected. In this paper, SEM, EDS, EBSD and TEM were used to characterize the micro-structure and composition of the two samples with and without CeO2 addition, and the anti-tribocorrosion resistance was studied in 3.5 wt% NaCl solution. The results show that the addition of 0.03% CeO2 can weaken the strong texture of LPBF-NiTi alloy in the direction of (001), but also plays a role in refining grain. Meanwhile, the formation of a new NiCe phase and lattice distortion was found in TEM. In addition, the addition of 0.03% CeO2 improves the anti-tribocorrosion resistance of LPBF-NiTi alloy in 3.5%NaCl solution significantly.