Author(s)

F. Djavanroodi & K. Nikbin

Abstract

High temperature crack growth in low alloy steels and nickel-base superalloys under static and cyclic loading F. Djavanroodi," K. Nikbin* ° Mechanical Engineering, Iran University of Science and Technology, Tehran, Iran * Mechanical Engineering, Imperial College, London SW72BX, UK ABSTRACT Many engineering components such as gas turbine discs, blades and guide vanes in modern power plant operating are subjected to combined steady and cyclic loadings which can give rise to creep, fatigue and combined creep/fatigue failure. In this paper crack growth behaviour at elevated temperatures under combinations of creep, creep fatigue and fatigue are investigated for a number of materials. Attention is focussed on the so-called intermediate (steady state stage 2) region of cracking. It is shown that for static and low frequency tests (<0.1Hz in general) where intergranular creep processes dominate, good correlations were obtained between the crack growth rate and the

Keywords