Enhancement of Yield Criteria Considering Anisotropic Behaviors of Sheet Metals

Limitations in the commonly used anisotropic yield criteria of sheet metals, such as Hill's 1948 and Hosford's 1979, are discussed in this paper. Analyses demonstrate that the commonly used yield criteria do not satisfy simultaneously the uniaxial tensile test data in rolling, transverse and diagonal directions and equibiaxial tension data. In order for the existing anisotropic yield criteria to fit experimental data in all the orientations, an enhanced method and an associated yield criterion are proposed. The method proposed can also be used to modify various anisotropic yield criteria in order to fit more material test data.