Abstract: This feasibility of application of Strain Energy Partitioning (SEP), Strain Range Partitioning(SRP), Ostergren M(OM) and Frequence Modified method(FM) to tension-tension stress condition were discussed. In case of the hysteresis loop half-opened, strain components for life prediction obtained by means of experiment measurement had been analysed. The effectiveness and predictcapability by using Numerical Computational Method of SEP (SEP-NCM) were described.

Key words: tension-tension stress, strain energy model, creep-fatigue, numerical compute