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arXiv · 1609.08191

Modeling the thermo-mechanical behavior of a woven ceramic matrix composite at high temperatures

Abstract

This paper aimed at extending a model developed by Ladeveze to capture thermal expansion and coupled thermo-mechanical phenomena, as such as those encountered at elevated and extreme temperatures. In the new model a linear thermal expansion coefficient is added to equation of state to account for the thermal to mechanical coupling effects. The mechanical to thermal effects are introduced by assuming an internal heat generation due to residual strain effects. The constitutive relations of the coupled thermo-mechanical behaviors of ceramic matrix composite material model were incorporated into Abaqus finite element code as user defined material software. An extension of the methodology presented by Letombes to calibrate the ceramic matrix composite damage model parameters based on a woven silicon-carbide silicon-carbide material developed by Safran Group. Feasibility tests (tension-compression, tension-tension cyclic, simple tension tests) based on a dog bone and open hole specimen tests demonstrated a good capturing of nonlinear as well as coupled thermos-mechanical behaviors in the silicon-carbide silicon-carbide material.

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Koffi Enakoutsa, Youssef Hammi, John E. Crawford, Joseph Abraham, Joe Magallanes. 2016-09-26. Modeling the thermo-mechanical behavior of a woven ceramic matrix composite at high temperatures. https://arxiv.org/abs/1609.08191

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