Simulation Study On Formation Mechanism And Wheel Wear Of Superhigh-point Grinding

Superhigh-point grinding is more advanced and more efficiency as a method of super-high speed grinding, which integrates super abrasive wheel, super-high speed grinding and CNC technology. Its main grinding properties are low grinding forces and temperature and now it is mainly used in grinding shafts. Now the process has been applied in automobile and tool manufacturing abroad. But, there are few information and reports about the research on the mechanism and process of the new technology in the world. Some vehicles manufacturing groups in China have introduced this new technique to machine single part with better benefits. Because they have not possessed the key technologies and the theories of quick-point grinding, the whole equipment and the correlative technologies have to rely on import, and the applying fields of the grinding process are limited. Therefore, the grinding mechanism and some key technologies of quick-point grinding need to study and explore more. In China, it is necessary to research the theories and the applications of quick-point grinding deeply and master the advanced technologies for improving the equipment manufacturing technologies.The basic working principle of superhigh-point grinding is:there are angles between the axis of workpiece and the axis of wheel in two directions, both in the horizontal plane and in the vertical plane. The purpose is making the contact area of the wheel and the workpiece being only a point. And the grinding wheel can be controlled by CNC system to grind the whole complicated cylindrical surface. Since the point-grinding angles existence in quick-point grinding, it is the point contact between the wheel and the work-piece. The mechanisms of generating surface and materials removal, wear performance of the wheel in the process is different from those in conventional cylindrical grinding process. Because of point-grinding angles, there are effects on contact layer model, grinding force and heat, work surface integrity and wear performance. Firstly, this paper gives an overview of the development the characteristic and the application of super-high speed grinding and quick-point grinding, summarizes the related technology and machine characteristics of quick-point grinding. With the actual development of quick-point grinding, the content and significance of the topic research were also introduced. On the basis of the analysis of principle and mechanism of superhigh-point grinding, the characteristics of superhigh-point grinding and wheel, especially the special character of wheel cutting point, were researched.Secondly, this paper emphasizes particularly on the abrasive geometry analysis on the quick-point grinding. After founding a model, this paper has educed equivalent wheel diameter, maximum contact length, undeformed chip thickness, and so on. The area of contact zone was analyzed and simulated, and the rule of point-grinding angles and grinding depth affects the form and area of contact zone were summarized.Then, with the characteristics of superhigh-point grinding and analysis of wheel wear, main factors affects wheel wear were researched, the rule of wheel wear is obtained, and the way to reduce wheel wear were advanced.At last, the accuracy and surface quality of superhigh-point grinding were researched, size precision and surface roughness in quick-point grinding are investigated, and the effective mechanism of some important parameters on them are studied, the way to higher size precision and lower size precision are discussed. Key words:Quick-point grinding; Superhigh-point grinding; contact zone; wheel wear; surface roughness...