Original paper(Vol.45 No.10 pp.1102)

Thermal fatigue life assessment for cylindrical component

Ichikawa Kunihiro; Sakurai Shigeo; Matsuda Noriaki; Fukuda Yoshio

Abstract:In order to develop a thermal fatigue life assessment method for high temperature components, out-of-phase thermal fatigue tests were carried out using cylindrical specimens of cobalt-based superalloy HA188 under various temperature ranges. The experiments were conducted in the temperature ranges peaking at 1000 degree while starting at 350 degree, 760 degree and 900 degree. A unique testing method was used in which thermal gradients were generated by induction heating for one edge of the specimen and water cooling for the inner and outer surfaces. The results of thermal fatigue test correspond well with the plastic strain range-life data of standard isothermal tests conducted at the peak temperature.

Key Words:thermal fatigue, crack propagation, life assessment, superalloy, FEM