Extrapolation methods: development, application and validation of novel methods: advanced testing concepts

Abstract

To allow for an accelerated determination of creep properties, several analytically based as well as experimentally based extrapolation methods have been developed in the past. In contrast to experimental methods, analytical methods are already introduced and genuinely used in praxis. Especially in the context of creep of metallic high temperature materials fundamental research work providing guidelines and concepts for the application of experimentally based extrapolation methods are strongly demanded, yet missing. With that, this publication focuses on the examination of experimentally based extrapolation methods particularly with regard to accelerated determination of creep properties required for high temperature applications. Results and conclusions of recently finished research works will be presented, which subjected a variety of accelerated testing methods on the basis of comprehensive experimental testing programs. Individual influencing factors and sensitivities as well as the application possibilities and restrictions regarding different types of heat resistant steels were determined and discussed. . Abbreviations ACT: Accelerated Creep Test; CA: Combinatory Approach; CCT: Conventional Creep Test; tu, tp1: Rupture Time, Time to 1% Strain; MAT Main Application Temperature; r1,r2,r3: Variants of Accelerated Creep Test; MG: Monkman-Grant; S1, …,S5: Step of Accel. Creep Test/Relaxation Test; ReT: Relaxation Test; Type A, …,E: Type of Combinatory Approach; TTP: Time-Temperature-Parameter