CHARACTERIZATION OF THE FRACTURE WORK FOR DUCTILE FILM UNDERGOING THE MICRO-SCRATCH

• 来源期刊: 力学学报（英文版）
• 学科: 物理学
• 年，卷（期）: 2002,（5）
• 页码范围: 494-505
• 页数: 12页
• 分类号: O3
• 语种: 英文

摘要

The interface adhesion strength (or interface toughness) of a thinfilm/substrate system is often assessed by the micro-scratch test. For a brittle filmmaterial, the interface adhesion strength is easily obtained through measuring thescratch driving forces. However, to measure the interface adhesion strength (or in-terface toughness) for a metal thin film material (the ductile material) by the micro-scratch test is very difficult, because intense plastic deformation is involved and theproblem is a three-dimensional elastic-plastic one. In the present research, usinga double-cohesive zone model, the failure characteristics of the thin film/substratesystem can be described and further simulated. For a steady-state scratching pro-cess, a three-dimensional elastic-plastic finite element method based on the doublecohesive zone model is developed and adopted, and the steady-state fracture workof the total system is calculated. The parameter relations between the horizontaldriving forces (or energy release rate of the scratching process) and the separationstrength of thin film/substrate interface, and the material shear strength, as well asthe material parameters are developed. Furthermore, a scratch experiment for theAl/Si film/substrate system is carried out and the failure mechanisms are explored.Finally, the prediction results are applied to a scratch experiment for the Pt/NiOmaterial system given in the literature.