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There are some universally difficult problems during the internal plasma spraying process,such as the substrate and spraying gun are more prone to be over-heated,and the coating performances meet for working requirement difficultly.The main reasons for these are the intemal spraying space is narrow,the temperature of plasma flame is very high,the dust and smog are driven out difficultly and the coatings are easily to be contaminated during these driven out.In order to obtain the high-performance internal plasma sprayed coatings on internal surface of φ150 cylinder of high-power engine,in this paper,the spraying process was optimized and designed,and a special installation was developed to function as dust-exhaust,dust-screen and cooling,after the high-energy internal plasma spraying gun was developed by the project group.The Ni45+15%Mo coating was prepared on the surface of internal cylinder.Through monitoring the substrate temperature during spraying process,testing the bonding strength of coating and analyzing the coating porosity and micro-structure,it can be concluded that the high-performance internal coatings can be obtained by properly designing spraying process and using the special spraying installation.These topics can provide some important insights into preparing the well anti-attrition and wear-resistance coatings on internal surface of the cylinder.