表面技术2025,Vol.54Issue(20):182-195,14.DOI:10.16490/j.cnki.issn.1001-3660.2025.20.013
SiC陶瓷纵扭超声磨削表面亚表面损伤及其试验研究
Surface and Subsurface Damage Mechanism and Experiment of Silicon Carbide Ceramics by Longitudinal-torsional Ultrasonic Assisted Grinding
摘要
Abstract
Silicon carbide ceramic is widely applied in high-performance parts such as high-temperature bearings,turbine blades,high-temperature corrosion-resistant components,and electronic devices due to its good wear resistance,thermal conductivity,low coefficient of expansion,oxidation resistance,and excellent high-temperature mechanical properties.However,it is difficult to achieve the precision machining through traditional grinding due to its high hardness,high strength,and high brittleness,and it is easy to cause high grinding force,high grinding heat,and many micro-cracks during traditional grinding,which affects its processing accuracy and reduces the working intensity and service life of the workpiece.Under the background,the longitudinal-torsional ultrasonic vibration assisted grinding(L-TUAG)is introduced into the ultra-precision grinding of silicon carbide ceramic parts,and its surface and subsurface damage mechanisms are investigated.Firstly,the kinematic trajectory equation of single abrasive grit and the cutting arc length model of single abrasive grit were established in L-TUAG,the special material removal mechanism was analyzed,the model of the maximum undeformed cutting thickness of single abrasive grit was constructed,and then the strain rate model and dynamic fracture toughness model of silicon carbide ceramic materials were respectively given.Based on the above models,the normal force model of single abrasive grit was established during L-TUAG,and the effect law of grinding force under different process parameters was analyzed.The analysis results showed that the normal grinding force of single abrasive grit decreased with the increase of grinding wheel speed,ultrasonic amplitude and material strain rate,and the normal grinding force of single abrasive grit increased with the increase of feed rate and grinding depth during L-TUAG.On this basis,the maximum subsurface damage model of SiC ceramics was established during L-TUAG.Secondly,based on the random distribution characteristics of diamond grinding wheel abrasive grit,the three-dimensional geometric model of multiple diamonds was established,and the simulation analysis of three-dimensional removal process of SiC ceramic under L-TUAG was carried out.Finally,the L-TUAG experiment of SiC ceramics was carried out.The theoretical analysis and experimental results showed that compared to traditional grinding,the actual cutting arc length of single abrasive grain increased because of the unique cutting trajectory during L-TUAG,and the maximum undeformed cutting thickness of single abrasive grain decreased,and then the strain rate and dynamic fracture toughness of the material increased.At the same time,the critical cutting depth for the brittle-plastic transition of SiC ceramics increased.As a result,its plastic removal area was expanded,and the surface and subsurface damage were reduced under the same machining parameters.In particular,the maximum subsurface damage depth was reduced by approximately 21.2%compared with traditional grinding.The maximum subsurface damage depth decreased with the increase of grinding wheel speed and ultrasonic amplitude,and increased with the increase of grinding depth and feed speed.The experimental values of the maximum subsurface damage depth were in good agreement with the theoretical values,with the maximum error rate of the model being 13.8%,and the average error rate being 8.4%.Therefore,it can be concluded that L-TUAG can significantly reduce the surface and surface damage of SiC ceramics,which provides the key theoretical support for achieving low-damage processing of silicon carbide ceramics.关键词
超声磨削SiC陶瓷/临界切削深度/应变率/动态断裂韧性/表面亚表面损伤Key words
ultrasonic grinding of SiC ceramics/critical cutting depth/strain rate/dynamic fracture toughness/surface and subsurface damage分类
矿业与冶金引用本文复制引用
闫艳燕,袁登科,张奇朋..SiC陶瓷纵扭超声磨削表面亚表面损伤及其试验研究[J].表面技术,2025,54(20):182-195,14.基金项目
国家自然科学基金(52475447)The National Natural Science Foundation of China(52475447) (52475447)