High-temperature corrosion-fatigue (circumferential) cracking life evaluation procedure for low alloy (Cr-Mo) boiler tube steels

A laboratory simulation procedure for reproducing high-temperature cracks found in coalfired boiler tubes was developed. The procedure design was based on an intergranular corrosion/thermal stress interactive initiation mechanism and an environmentally assisted fatigue crack propagation mechanism. Simulation results show the potential of this procedure as both an evaluation tool for material solutions to the problem and a life estimation procedure for new boiler tube surface modifications.