| 摘要: |
| 断裂强度受到磨削表面微观形貌和残余应力场分布的影响。对Si3N4、SiC和Al2O3陶瓷材料实施平面磨削后，用金相显微镜、表面轮廓仪和X射线应力测试仪研究陶瓷机械抛光前后表面微观形貌、粗糙度、残余应力与工件磨削断裂强度的关系。结果表明：经无水乙醇润滑抛光后SiC陶瓷具有平滑的表面微观形貌、较低的表面粗糙度和残余应力；反应烧结的Si3N4、SiC和Al2O3陶瓷磨削并抛光20 min后的断裂强度幅度依次为6.64%、8.18%和6.58%；适当的抛光时间能降低陶瓷磨削表面应力集中程度及残余拉应力，使陶瓷的断裂强度得到一定提升。 |
| 关键词: 工程陶瓷 磨削 表面抛光 断裂强度 残余应力 |
| DOI： |
| 分类号: |
| 基金项目:国家自然科学基金(51105378); 国防十二五预研项目(51318020210) |
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| Influences of Surface Polishing on Fracture Strength for Ground Engineering Ceramics |
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WANG Jian-quan, TIAN Xin-li, ZHANG Bao-guo, WANG Peng-xiao1,2
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1. Science and Technology on Remanufacturing Laboratory, Academy of Armored Force Engineering, Beijing 100072;2. China Astronaut Research and Training Center, Beijing 100094
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| Abstract: |
| The Fracture strength of engineering ceramics is significantly influenced by the microscopic topography and residual stress field of ground surface. In this research, several testing equipments, such as metallurgical microscope, surface profiler and X-ray residual stress tester were adopted to investigate the relationships between microscopic topography, surface roughness, residual stress and fracture strength of ground ceramics, after surface grinding and mechanical polishing.Experimental results show that the smoother machined surface with low roughness and residual stress is obtained by polishing with absolute alcohol for 20 minutes; the fracture strength of Si3N4, SiC, and Al2O3 increases by 6.64%, 8.18%, and 6.58%， respectively, compared with the work pieces without polishing, and the surface stress concentration and residual tensile stress of polished ceramics are both reduced after an appropriate polishing time, which causes a certain improvement of the fracture strength. |
| Key words: engineering ceramics grinding surface polishing fracture strength residual stress |
