Study on tribological properties of pseudoelastic Ti-Ni alloys with laser surface micro-convexes

Micro-convexes on Ti-Ni shape memory alloy surface were produced with laser. Their tribological properties were evaluated with a pin-on-disc tester under various loads and velocities. The results show that surface convexes can reduce the friction coefficient obviously under lubricated conditions. The top amount of friction coefficient reduction rate is up to 44.6% on the disc with low surface convex density while the initial contact pressure is 0.21 MPa and the velocity is 0.25 m/s. The anti-wear property of the discs with convexes is better than that without convexes. The anti-wear property of the disc with high surface convex density is the best in all convex discs. The grooves surrounding the convexes can trap debris and be beneficial to control surface ploughs and improve wear resistance.