Chaboche anisotropic viscoplastic constitutive equations were rewritten and the implicit stress integration algorithm was obtained by the governing parameters method.In the algorithm

all the unknowns were expressed by the same parameterwhich forms a governing equation.Therefore

the problem integrating stress was changed into one solving nonlinear equation.This algorithm procedure was embedded in the finite element program Marc

and the experiment examples of uniaxial tension

cyclic loading and relax mean stress relaxation were simulated on single element.From the comparison of implicit algorithm with the explicit one

the results show improvement in steadiness and convergence.The comparisons conducted on component finite element calculations also show that implicit algorithm has higher efficiency than explicit one.