ISO/WD TS 4596

Metallic materials — High temperature creep/fatigue crack growth testing method

Scope

This document specifies a method of testing for measuring and analysing Creep Crack Initiation (CCI), Creep Crack Growth (CCG), and Creep Fatigue Crack Growth (CFCG) characteristics using a wide range of specimen geometries of parent as-received and welded. The CCI, CCG, CFCG characteristics are correlated with fracture mechanics parameter K, C* etc. Specimens considered in this document are shown in Annex A.1, and their parameters are shown in Annex A.2. The list of geometries is not by any means complete and the user is advised to use appropriate information from other databases for other geometries to derive the relevant fracture mechanics parameters to use in the analysis. The validation of the parameters that are to be used however is important, especially where concern exists regarding the compatibility of test geometry with the actual component in terms of size, the type of loading and stress state. This document allows flexibility and a wide choice of specimen geometries than available without comprising on the important issues such as accuracy of testing and data measurements and the appropriate derivation of the correlating parameter. Less emphasis and detail have been placed on cycle dependent fatigue test methods compared to time dependent creep test methods as fatigue testing has been comprehensively dealt with in other standards and the parameters needed for its analysis are linear elastic in nature and therefore, simpler than the non-linear time dependent creep regime.