Abstract
Two approaches to the choice of testing conditions with the effect of simultaneous control over thermal and thermally stressed states of specimens which provide the induction of preset uniaxial and biaxial unsteady stressed states were analyzed and developed. The first approach is based on inducing thermal stresses in a cyclically heated specimen by restraining force and mechanical loads. The second approach is based on inducing thermal stresses in a massive specimen free of external mechanical loads in a natural way due to a nonuniform temperature distribution over its volume, also accounting for the requirement of inducing the states corresponding to unsteady states of real massive structural elements. Specimens consisting of two concentric massive rings connected with a thin neck were demonstrated to be effective for thermal fatigue testing of high-temperature materials used in gas turbines. State vs geometry curves are plotted, and a method of determining the dimensions of ring specimens to produce preset thermal and thermally stressed states of the material is described.
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Additional information
Institute for Problems of Strength, National Academy of Sciences of Ukraine, Kiev, Ukraine. Translated from Problemy Prochnosti, No. 4, pp. 67–81, July–August, 1997.
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Tretyachenko, G.N., Karpinos, B.S., Barilo, V.G. et al. Induction of preset thermally stressed states in thermal fatigue tests: Choice of testing conditions and geometry of specimens. Strength Mater 29, 369–379 (1997). https://doi.org/10.1007/BF02767822
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DOI: https://doi.org/10.1007/BF02767822