TY - JOUR ID - 71288 TI - Prediction of Instability in Planar Anisotropic Sheet Metal Forming Processes JO - International Journal of Engineering JA - IJE LA - en SN - 1025-2495 AU - Farzin, M. AU - Hashemolhoseini, H. AD - , Isfahan University of Technology Y1 - 2001 PY - 2001 VL - 14 IS - 1 SP - 69 EP - 80 KW - Sheet Metal Forming KW - Instability KW - bifurcation KW - Planar Anisotropy KW - Large Deformation KW - Necking DO - N2 - In this paper instability of planar anisotropic sheet metal during a few forming processes is investigated for the first time. For this reason components of the constitutive tangent tensor for planar anisotropic sheets are developed. By using the above tensor location of necking is predicted. Direction of the shear band is also predicted using the acoustic tensor. A finite element program is prepared based on large deformations of planar anisotropic sheet metals. In this program rotations of principal directions of anisotropy are also taken in to account. Results obtained from the presented model are in good agreement with experimental observations. UR - https://www.ije.ir/article_71288.html L1 - https://www.ije.ir/article_71288_6e4a83e69a9d7cd0e61aeaf0b84e759b.pdf ER -