relationships to be temperature insensitive to within a factor of two on cyclic life. Monotonic creep and tensile ductilities were also found to be temperature insensitive to'within a' factor of two.The approach provides bounds on cyclic life that can be readily established for any type of inelastic strain cycle. Continuous strain cycling results obtained over a broad range of high temperatures and frequencies are in excellent agreement with bounds provided by the approach.The observed transition from one bound to the other is also in good , agreement with the approach.

No abstract

A general method is presented for the solution of creep problems by the use of successive approximations. The method is equally applicable to different creep laws and loading paths. Examples are presented for the creep in a flat plate with a temperature gradient and for several cases of rotating disks. In these disk problems the transient conditions prior to the establishment of steady-state stress distribution are included and shown to have an appreciable effect on the total creep strains. The use of different cumulative creep laws such as the time-hardening and strain-hardening laws are illustrated.