Volume 3 Issue 3
Authors: Jie Yang; Yuejin Ma; Jianguo Zhao; Jianchang Li; Jianjun Hao
Abstract: Wear is one of the primary failure modes in the materials field which causes huge economic losses each year. The life of agricultural tools is significantly shortened by wear. However, due to the structure and performance needs of their materials, agricultural tools made of high strength and high hardness materials may be unable to meet the requirements of agricultural production, and come at very high cost. This is one of the problems faced by Chinese agriculture. In materials manufacturing and repairing processes, plasma spraying is a common technology. Plasma spraying is an effective mean of obtaining a material surface functional coating with high efficiency, high quality, a wide range of spray materials, and low cost. In order to improve the wear resistance of the material through orthogonal testing and variance analysis, we prepared Ti/Al2O3 composite coatings on ordinary carbon steel Q235 matrices using plasma spray technology, ZB-80 plasma spraying equipment, an MH-6 micro-hardness tester, an HSR-2M reciprocating friction and wear testing machine, scanning electron microscopy (SEM), and a WS-2005 automatic coating adhesion scratch tester. Results demonstrated the effects of spray current, spray voltage, spray distance and volume fraction of Ti on the performance of the coating, then obtained and verified optimal process parameters. The optimal process parameters are as follows: spray current = 690A, spray voltage = 65V, spray distance = 80 mm and volume fraction of Ti = 40%. Under the optimal process parameters, we obtained the 10# specimen and verified its performance. The wear resistance and hardness of the 10# specimen was greatly improved. The microstructure and properties of agricultural tools were significantly improved after plasma spraying.
Keywords: Plasma Spraying; Composite Coating; Ti/Al2O3; Wear Resistance; Micro-Hardness; Bond Strength