Comparative analysis of three thermal fatigue experiments
This paper presents an analysis of the ability of different criteria to predict fatigue crack initiation under thermal loading. More precisely the predictions of the number of cycles to crack initiation are compared with experimental results obtained using five different fatigue criteria in three types of thermal fatigue tests (namely the FAT3D, JRC and SPLASH test campaigns).
This analysis has revealed that:
• The conventional criteria based on equivalent strain variation substantially overestimate the lifespan of a structure subjected to thermal loading.
• A criterion making account for loading multiaxiality is required to estimate thermal fatigue life.
Three of the criteria studied give satisfactory results: the Zamrik criterion, the Park and Nelson criterion and a criterion taking hydrostatic pressure into consideration proposed by Amiable et al. The latter should be preferred for the accuracy of its results and the Zamrik criterion for its simplicity.
Document Type: Research Article
Publication date: September 1, 2008