Flat-tipped Indentation Fracture Mechanics
A singular stress field exists in an elastic substrate around the contact edge with a rigid flat-tipped indenter.This surface-contact-induced singular stress field can also be described by the stress intensity factor concept,if the indentation stress intensity factor Kind is introduced for indentation cracking analysis.The Kind–controlled singular stress field is almost identical to that of the Mode-Ⅰ tensile singular stress field around the crack tip,except the negative sign due to the compressive nature of surface contact loading.This study presents an energy-based fracture mechanics analysis for the indentation stress intensity factor (ISIF) Kind and the indentation-induced boundary cracking within the Kind-dominant region around the contact edge.It is found that the critical indentation stress intensity factor exists,and the relation between the indentation fracture toughness KIC-ind and the common Mode-I fracture toughness KIC is established analytically,showing KIC-ind = 2.5KIC.The indentation-cracking angle at the contact edge is also determined.The fracture mechanics model on surface contact cracking induced by a flat-tipped indenter provides a useful alternative for measuring the fracture toughness KIC,which can be useful for characterization of surface fracture properties of bulk elastic bodies and coating fracture properties of layered structures such as MEMS.
Indentation Indentation fracture toughness Contact mechanics Surface cracking
Xiaozhi Hu Yujun Xie
School of Mechanical and Chemical Engineering,University of Western Australia,Perth,WA 6009,Australi Department of Mechanical Engineering,Liaoning Shihua University,Fushun,113001,P.R.China
国际会议
北京
英文
1-9
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）