Effects of Nitride on the Tribological Properties of the Low Carbon Alloy Steel

The technology of composite heat treatment is used popularly for low friction and wear resistance of drive elements. A large number of papers about the heat treatment technology had been proposed. Especially, the nitride treatment has been used widely for the purpose of wear resistance and low friction in the industry. Therefore, the self-developed vertical ball/disk friction tester with the measurement system was used to study the effects of nitride on the tribological properties of the low carbon alloy steel—SCM415— in this study. The experiments were conducted under dry and severe wear conditions. The variations of friction coefficient and surface magnetization were simultaneously recorded during dynamic friction process. After each test, the microstructures of the wear particles were observed and analyzed under a SEM, and the depth of wear track is measured by means of a surface tester. According to the experimental results, the wear resistance of the specimens with carburizing-nitride is significantly larger than the case of nitride-carburizing. Moreover, the surface magnetization was especially larger for the case of nitride-carburizing. As a result, the wear particles always stay in the interfaces and the wear mechanism becomes complex. Therefore, it is necessary to put nitride after carburizing for the composite heat treatments. 1. Introduction The performance of high quality and high accuracy is very important for the high accurate mechanical engineering. Hence, the drive elements play an important role when it was used in the actuator of the machine. Moreover, the high performance of low friction and wear resistance for drive elements is very important for the actuator. In order to achieve the above goal, the technology of composite heat treatment is attracted recently for the industry [1, 2]. A large number of papers about the composite heat treatment technology had been proposed [3, 4]. Especially, the nitride treatment has been used widely for the purpose of wear-resistance and long fatigue life in the industry [5, 6]. The tool steels containing Al or Cr by the nitride treatment are considered as a wise method for improving the surface hardness and the strength near the middle of the materials [7]. Therefore, the nitride treatment is always used to make surface hardening and improve wear resistance, fatigue life, and corrosion resistance for the tool steels [8, 9]. Since the authors had experimentally studied the tribological properties of the pair of iron with the carbon steels in depth [10–13], the knowledge is applied and adapted to the