To reveal the differences in tribo-corrosion resistance of TC4 alloys with different orientations prepared by selective laser melting technology (SLM) in the body fluid environment,the tribo-corrosion properties of the TC4 alloy samples with different orientations (0°,45°,90°) and the traditional forged TC4 alloy sample were studied in PBS phosphate buffer by a combined electrochemical tribo-corrosion test method at the load from 0.3 N to 1.0 N.The results show that the SLM TC4 alloy samples are mainly composed of fine aciculateα′phase (hcp) and a small amount ofβphase (bcc) in different orientations,resulting in the average microhardness of SLM samples is significantly higher than that of forged TC4 alloy.There is a slight difference in phase content ofα′phase andβphase for the samples in different orientations,and the 0° oriented samples exhibit the highest mean microhardness due to the largest amount of α′phase.The main wear mechanism of TC4 alloy is abrasive wear at low load and tribo-corrosion at high load,and the 0°oriented SLM sample shows the highest corrosion resistance and tribo-corrosion resistance due to its large and uniform fine high-strength acicular α′phase.At the load of 0.5 N,the four samples studied show the largest difference in wear rate,and the wear rate of the 0°oriented sample decreases by 41.6%,54.7%,and 75.7% compared to the 45°and 90°oriented samples,and forged TC4 alloy sample,respectively.It can be concluded that the anisotropy of additive manufactured TC4 alloy affects the tribo-corrosion property obviously.This has certain reference significance in optimizing the structural design of additive manufacturing in order to improve the corrosion and wear performance of specific friction surfaces in medical implants.