Modelling the multiaxial creep behaviour of Alloy 800H
A creep constitutive model based upon the theta-projection concept is derived, using constant stress creep curves obtained from miniature creep specimens cut from the walls of Alloy 800H tubing. Initial verification of the model predictions under changing uniaxial stress conditions is made by comparison with a series of constant load creep results. Two multiaxial constitutive models have been developed based on the theta description of uniaxial behaviour, the first based on a von Mises function of equivalent stress and the second based on the maximum principal stress criterion. These models are used to predict the creep deformation and rupture behaviour of tubular specimens under combined internal pressure and axial load. It is shown that both the multiaxial creep deformation and rupture behaviour of Alloy 800H at 900 C are predicted accurately by the model based on the maximum principal stress criterion.
Bibliographic Reference: Article: International Journal of Pressure Vessels and Piping, Vol. 47 (1991) pp. 355-370
Record Number: 199111487 / Last updated on: 1994-12-02
Original language: en
Available languages: en