Strain field and strain history of nonproportional loading

摘要

Nonproportional multiaxial loading of components is of great interest in fatigue and damage studies. To present a complete strain field and strain history of such loading, an incremental theory of plasticity should be employed. However, due to its incremental nature, the computational time is not favourable. On the other hand the total deformation plasticity is less time consuming but is path independent and hence is not capable of predicting strain history. Also the strain predictions are not correct. In this paper an appropriate path dependent semi total deformation method is presented for nonproportional loading. In the formulation presented both linear and nonlinear stressing is considered. Different examples are considered and results obtained from present method are compared to incremental plasticity using finite element method.