An interpolation type anisotropic yield function and its application in sheet metal forming simulation

Affected by texture, Bauschinger effect and different deformation mechanisms, plastic deformation behavior of the sheet metals are complicated, especially for HCP metals, such as magnesium and titanium. With more and more enhanced demand to describe the materials' yield behavior precisely and efficiently in numerical simulation, application of traditional continuous type yield functions encounters great challenge. So an interpolation type anisotropic yield function for plane stress is proposed. This yield function is represented by a yield surface in the polar coordinate system. The radius vector to the yield surface represents the yield stress at yielding, while the outer normal is related with the R values. The physical meaning of the parameters is directly defined. Accuracy, efficiency and flexibility can be achieved by application of such yield functions.