Constitutive Modelling of CMCs for Non-proportional, Multi-Axial Loadings

Abstract

The aim of this study was to explore the possibility of identifying a mechanical non-linear constitutive law from experimental data obtainedon oxide/oxide composite tubes presenting an involute meso-structure. For that, a damage model previously developed for ceramicmatrix composites was presupposed. For simple loading cases, the model describes correctly the experimental results. For some shearcomponents, the available data was not sufficient. Regarding multi-axial loadings (tension-torsion), the available experimental informationdidn't allow a robust identification. This work has shown that the proposed model may be adapted to represent experimental resultsobtained from oxide/oxide composites. Due to the involute meso-structure of the different coupons, the use of a model is necessary toclearly understand the role of the different loading conditions. Before going further with the model, it seems that the experimental resultsshow a rather large scattering in the obtained values. Further work should be conducted to give more robustness to these tests. It shouldresolve the doubts one can have on the proposed evolutions laws for tension-torsion loadings. Other modeling perspectives are related tothe implementation of the model and the description of macroscopic rupture. In the model, there are two origins for failure: 1. fibers reachtheir capacity to carry the load, as in the case for pure tension; 2. an unstable mechanism develops, as is the case for shear loadings. Thefirst origin can be easily described by a criterion while the second is already introduced in the model via the evolution laws.

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Document Details

Document Type
Technical Report
Publication Date
Jun 03, 2020
Accession Number
AD1106369

Entities

People

  • Emmanuel Baranger

Organizations

  • École Normale Supérieure

Tags

Communities of Interest

  • Air Platforms
  • C4I
  • Space

DTIC Thesaurus Topics

  • Air Force
  • Air Force Research Laboratories
  • Ceramic Matrix Composites
  • Composite Materials
  • Experimental Data
  • High Temperature
  • Identification
  • Law
  • Materials
  • Mechanics
  • Modulus Of Elasticity
  • Orientation (Direction)
  • Shear Modulus
  • Shear Stresses
  • Stiffness
  • Stress Strain Relations
  • Stresses

Readers

  • Data Mining and Knowledge Discovery.
  • Mechanical Engineering/Mechanics of Materials.
  • Structural Health Monitoring of Composite Structures.