反应烧结SiC陶瓷脆性去除特征及刻划力波动行为  

Removal characteristics and fluctuation behavior of cutting force during scratch process of RB-SiC ceramics

作　　者：李志鹏 张飞虎[1] 孟彬彬[1] LI Zhi-Peng;ZHANG Fei-Hu;Meng Bin-Bin(School of Mechatronics Engineering,Harbin Institute of Technology, Harbin 150001,China)

机构地区：[1]哈尔滨工业大学机电工程学院,黑龙江哈尔滨150001

出　　处：《光学精密工程》2018年第3期632-639,共8页Optics and Precision Engineering

基　　金：国家973重点基础研究发展计划资助项目(No.2011CB013202);国家重点研发计划资助项目(No.2016YFB1102204)

摘　　要：主要研究不同加工深度及压头形状刻划条件下反应烧结碳化硅(RB-SiC)陶瓷脆性去除特征和刻划力波动行为之间的关系。采用半径分别为400nm的金刚石玻氏压头以及8.7μm的圆锥压头进行恒切深刻划,并利用扫描电子显微镜对刻划后的SiC陶瓷表面进行测量。最后,通过Daubechies小波进行横向力和切向力信号分解,并结合划痕表面损伤形式,给出不同细节信号及近似信号与加工损伤的联系。实验结果表明:对于圆锥压头,随着加工深度的增大,表面形貌为塑性挤出、微破碎和大面积表面破碎共存的形式。此外,在脆性断裂去除情况下,随着压头尖端半径的减小,破碎程度增加且刻划力信号能量由低频段逐渐扩散到整个频域。同时低频段的能量逐渐占据主要地位。不同程度的表面微破碎及边缘微破碎对刻划力细节信号分量贡献较大。反应烧结碳化硅结构本身差异以及缺陷引起的大面积断裂是刻划力波动能量的主要来源,而且随着加工深度的增大而增大。This paper aims to explore the brittle fracture characteristics and fluctuation behavior of cutting force during scratch process of RB-SiC with different scratch depth and indenter shapes.The diamond Berkvoich indenter with 400 nm and conical indenter with 8.7 um were used to conduct experiments under constant scratch depth mode.Then,the surface morphologies and brittle fracture behavior were observed with a scan electron microscopy(SEM).Finally,Daubechies wavelet was adopted to decompose the lateral and tangential forces,and the relationship between different detail signal/decompose signal and damage types were given.The results show that with the increasing of scratch depth,plastic extrusion,micro fracture and large area fracture are coexist when conical indenter is used.Besides,the degree of fracture is more serious and cutting force signal energy spread from low-frequency to the whole frequency with the decrease of indenter radius and the energy of low-frequency band energy gradually occupied the dominates position.Surface and margin microfracture make the dominate contribution to the detail signal of cutting force.Scratching force fluctuation energy is mainly come from the structure difference and defects of RB-SiC which caused mass crushing,and increased with scratch depth.

关 键 词：RB-SIC 脆性断裂 小波分析 刻划力 玻氏压头 圆锥压头 

分 类 号：P228.5.1[天文地球—大地测量学与测量工程]