Effect of Ni/MoS2 Addition on Microstructure and Properties of Supersonic Plasma-Sprayed Ni-Based Composite Coatings

Abstract

Abnormal tool wear is a significant problem encountered in machining. MoS₂ has the function of friction reduction; thus, to mitigate friction, two Ni-based coatings, Ni60 and Ni60 + 15 wt.% Ni/MoS₂, were obtained on tungsten steel using supersonic plasma technology. The microstructure, phase structure, microhardness, fatigue properties, and friction and wear properties of the two coatings were characterized. The results show that the two plasma-sprayed Ni-based coatings have desirable structures. The addition of Ni-coated MoS₂ can effectively improve the hardness of the coatings, with values reaching as high as 735 HV. The speed of rotation of the friction ball was set as 200 r/min, and the cutting force was 201.6 N. The fatigue performance as well as the friction and wear performance of the coating are simulated using ANSYS. The fatigue performance is improved by 12.6 % after adding 15 wt.% Ni/MoS₂, and the friction system of the coating becomes stable after 25 min of contact. The addition of 15 wt.% Ni/MoS₂ can effectively improve the performance of the tool material.