Plastic flow localization in mechanism-based strain gradient plasticity

✍ Scribed by M.X. Shi; Y. Huang; K.C. Hwang

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 196 KB
• Volume: 42
• Category: Article
• ISSN: 0020-7403
• DOI: 10.1016/s0020-7403(00)00009-6

✦ Synopsis

The theory of mechanism-based strain gradient (MSG) plasticity is used to study plastic #ow localization in ductile materials. Unlike classical plasticity, the thickness of the shear band in MSG plasticity can be determined analytically from a bifurcation analysis, and the shear band thickness is directly proportional to the intrinsic material length, ( / 7

)b associated with strain gradients, where is the shear modulus, 7 is the yield stress, and b is the Burgers vector. The shear band thickness also depends on the softening behavior of the material. The analytical solution of the shear strain rate yields that the maximum shear strain rate inside the shear band is two orders of magnitude higher than that outside, which is a clear indication of plastic #ow localization. The limitation of the present model is also discussed.