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In clinical practice,Ni-Ti endodontic files usually exhibited poor cutting efficiency due to their inferior wear resistance,when compared with the traditional stainless steel ones.Therefore,it arose us the idea of introducing Ni-W hard coating on top of Ni-Ti shape memory alloy by electrodeposition method.In the present study,Ni-W coatings were prepared from a Ni-W bath with a temperature of 70℃ and a pH value of 6.5 at different cathode current densities on Ni-Ti shape memory alloy by direct current electroplating technique.The as-deposit Ni-W coatings were characterized by the energy dispersive spectrometer (EDS),scanning electron microscopy (SEM) and X-ray diffractometer (XRD).The wear resistance of Ni-W coatings was calculated by the wear rate and the width of wear track after tested on a pin-on-disc wear machine.The results showed that as the current density increased,the tungsten content in Ni-W coatings increased from 32.6 wt.% to 34.4 wt.%,subsequently leading to an increase in microhardness and the sliding wear resistance.The heat treatment at 673K for 1h improved the adherence of Ni-W coating and enhanced the wear resistance.