Identification of parameters of non-viscous body deformation models by experimental creep curves

Authors: Izotov I.V.
Published in issue: #7(36)/2019
DOI: 10.18698/2541-8009-2019-7-498
Category: Mechanics | Chapter: Mechanics of Deformable Solid Body
Keywords: creep, deformation, operational life, creep models, creep tests, damage mechanisms, approximation of creep equations, finite element creep calculation
Published: 29.07.2019

This article presents the determination of the coefficients for the equations of two different creep models on the basis of creep experiments conducted earlier. The possibility of approximation of these equations for more complex loading conditions was established. The results obtained show that the Norton law, which is widespread for the approximation of creep, gives poor results in cases of load changes on the sample. At the same time, a law based on hyperbolic functions can significantly improve the accuracy of the estimation of the creep process development. The application of the obtained formulas and coefficients should lead to a more reliable prediction of the life of structures operating under conditions of high temperatures and loads.

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