金刚石与磨料磨具工程2025，Vol.45Issue(2)：176-188,13.DOI:10.13394/j.cnki.jgszz.2024.0030
碳化硅陶瓷的磨削损伤特性
Grinding damage characteristics of silicon carbide ceramics
摘要
Abstract
Objectives:To explore the grinding damage mechanism and surface/subsurface damage distribution law of silicon carbide ceramics.Methods:Combined with single-particle scratching experiments,grinding experiments,and fi-nite element simulation analyses,the critical stress value of the plastic-brittle transition of the material,as well as the trend of the influence of the grinding parameters on the damage distribution,are clarified.Results:The ultimate frac-ture strength of the silicon carbide ceramics used in this experiment is about 344 MPa,and the grain boundary fracture strength is about 25.9 MPa.Both the experimental and simulation results show that the microstructure of the material plays different roles under different loads.When the contact stress is less than the critical fracture strength of the grain boundaries,the grain boundary structure plays a viscous role,consuming stresses to inhibit the expansion of cracks.With a further increase in load,although not reaching the critical stress value of the grain boundaries,the cracks are still generated but not as severe.Further increase in load,although the material fracture limit is not reached,the material sur-face will still exhibit cracks and pits due to microstructural damage caused by grain boundaries,graphite,and pores.When the contact stress exceeds the critical strength of the material and the grain boundaries,the microstructure pro-motes the growth of cracks,further expanding the damage area of the SiC ceramics.In the paper,through the optimiza-tion of the grinding process parameters,the best parameters for achieving the minimum grit undeformed chip thickness and grinding force are determined,thus minimizing the percentage of material surface damage and the depth of subsur-face damage,which are 0.396%and 4.768 μm,respectively.Compared with the worst parameters,the damage values are only 16.01%and 13.22%of their respective counterparts.Conclusions:The process of material grinding damage is similar to that of single grit scratch damage,which progresses three stages:plastic removal,plastic-brittle removal,and brittle removal.The grinding force,the change in maximum grit thickness without deformation,and the extent of mater-ial damage all tend to increase with the increase of feed rate and grinding depth,and decrease with the increase of grind-ing wheel speed.The microstructure of ceramic materials is an important reason for their machining susceptibility to machining damage.In order to achieve low-defect processing of silicon carbide ceramics,it is not only necessary to op-timize the grinding process parameters but also to consider the role of the microstructure.The experimental results provide theoretical guidance for achieving low-damage and high-quality processing.关键词
碳化硅陶瓷/磨削加工/磨粒未变形最大磨屑厚度/表面/亚表面损伤Key words
silicon carbide ceramics/grinding processing/maximum undeformed abrasive debris thickness/surface/subsurface damage分类
通用工业技术引用本文复制引用
叶卉,谢家富,倪安杰..碳化硅陶瓷的磨削损伤特性[J].金刚石与磨料磨具工程,2025,45(2):176-188,13.基金项目
国家自然科学基金(62305221) （62305221）
上海市青年扬帆科技英才计划(18YF1417700) （18YF1417700）
教育部产学合作协同育人项目(220606071203633). （220606071203633）
