著者

西嶋 修 福原 直道 平方 寛之 米津 明生 箕島 弘二

出版者

一般社団法人日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2010, pp.10-11, 2010-10-09

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This study aims to elucidate the mechanics of crack propagation in a freestanding Cu thin film deposited by electron beam evaporation We developed the method for fabricating nano or submicron meter-thick freestanding metallic films with width and length of the miffimeter order. Focused ion beam (FIB) was employed to introduce a pre-crack in an about 500 nm-thick Cu film. It is found that the crack stably propagated by uniaxial tensile loading, and then the crack propagation rate rapidly increased, resulting in unstable fracture. The fracture surface suggested that the local area near the crack tip undergoes large plastic deformation, resulting in crack propagation in ductile manner. In parallel, the elastic-plastic stress distribution around the crack tip was analyzed by finite element method (FEM). The mechanics of crack propagation and fracture toughness were investigated on the basis of the R-curve concept.