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磨削过程中零件表层物理特性如金相组织、表面残余应力、磨削烧伤等的过程监测是为确保零件制造质量的重要课题,但目前尚难于在生产过程中实现。 在平面磨床上进行大量磨削16MoCr5表面硬化钢的试验后发现,单位面积磨削功率P″_c与砂轮—工件接触区最高平均温度T_(max)间有极好的函数对应关系。而磨削表层金相组织状态和发生烧伤主要决定于接触区的温度,因而可以应用相对容易测量计算的单位面积磨削功率P″_c来识别这些状态。如果P″_c没有超过某一特定的临界值P″_(cⅠ)时,磨削表层保持正常的针状马氏体组织。在超过P″_(cⅠ)的情况下,切向磨削力的斜率增加,当P″_c又超过第二临界值P″_(cⅡ)后,磨削表面由于烧伤而出现了变色层,表层金相组织和显微硬度证实了工件的这些不同的情况。试验结果表明,单位面积磨削功率P″_c,可以作为磨削过程监测和预报表层金相组织状态和磨削烧伤的可靠的过程特征参量,在生产实践中应用。
During the grinding process, surface physical properties of parts such as metallurgical structure, surface residual stress, grinding burns and other process monitoring is to ensure the quality of parts manufacturing an important issue, but it is difficult to achieve in the production process. A large number of ground grinding on a surface grinder 16MoCr5 case hardened steel test found that the unit area grinding power P “_c and wheel-workpiece contact zone maximum average temperature T_ (max) has a very good function of the relationship between the grinding The microstructure and burns of the surface layer are mainly determined by the temperature of the contact zone so that these conditions can be identified using a relatively easy measurement of the calculated grinding power P ”_c per unit area. If P “_c does not exceed a certain critical value P” _ (c Ⅰ), the ground surface to maintain normal acicular martensite. The slope of the tangential grinding force increases in excess of P “_ (c I). When P” _c exceeds the second critical value P “_ (c II), the grinding surface develops a discolored layer due to burns, The microstructure and microhardness of the surface layer confirm these different conditions of the workpiece.The results show that the grinding power P ”_c per unit area can be used as the grinding process to monitor and predict the microstructure of the surface layer and the reliability of grinding burns Process characteristic parameters, used in production practice.