Judges’ Queries and Presenter’s Replies

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Presentation Discussion

  • May 21, 2012 | 11:39 p.m.

    nice presentation and poster.

    I guess I wonder what was the main motivation for this study, particularly as it relates to the hybrid material that you chose model? In this regard, what are some applications for the data and models you generated?

  • Icon for: Brian Lester

    Brian Lester

    Presenter
    May 22, 2012 | 10:36 a.m.

    Professor Shin,

    the main application for the considered materials is high temperature, extreme flight conditions like those found in high speed (supersonic or hypersonic conditions), atmospheric reentry or in combustion chambers. By using the two specific constituent phases mentioned we hope to improve material performance (over past composites) through the development of residual stress states.

    The results of these analysis will be used in conjunction with collaborators designing the material to help in tailoring the manufacturing of the material.

  • Further posting is closed as the competition has ended.

Icon for: Brian Lester

BRIAN LESTER

Texas A&M University
Years in Grad School: 3

Modeling of Hybrid Shape Memory Alloy (SMA)- Ceramic Composites

A numerical model of a hybrid Shape Memory Alloy (SMA) – MAX phase ceramic composite is developed. To account for the different inelastic mechanisms found in the system, a recent 3D constitutive model for the SMA behavior and an elastic-plastic approximation of the MAX phase behavior are introduced. To study the effects of the microstructure on the system, a finite element mesh is generated from x-ray tomography results. By subjecting the composite to an isobaric actuation loading path, it is demonstrated that the effective composite response exhibits decreased transformation strains versus dense SMAs and that the associated transformation temperatures are shifted. Interestingly, through an actuation cycle, irrecoverable strains are generated in the MAX phase leading to a residual stress state in the composite. Such a stress state serves as a biasing load to take advantage of the ceramics superior mechanical response under compression.