On bifurcation of homogenous deformation in metallic glasses
At temperatures well below the glass transition and at high stresses,the homogenous deformation in metallic glasses (MGs) usually develops to a critical point,at which the discontinuity in deformation rate is incipient across nano-scale shear bands.However,such a bifurcation condition of homogeneous deformation concerning the unique properties of MGs is still lacking for general stress state.In this paper,a new constitutive is introduced for MGs accounting for the pressure-sensitivity,dilatancy and structural evolution; the shear banding is regarded as the appearance of instability in the constitutive description of inelastic deformation.Tying the bifurcation theory to the new model,the general condition of deformation localization is derived.The shear band initiation and failure orientation are then precisely predicted for MGs by constructing a bridge between the microscopic origin and the loss-of-ellipticity instability in the constitutive law in continuum mechanics.
Metallic glasses Bifurcation Shear band
Yan Chen Lanhong Dai
State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Science,Beijing,100190,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）