Thermal Fatigue Behavior of a Unidirectional SCS6/Ti-15-3 Metal Matrix Composite

Abstract

Damage mechanisms in a unidirectional titanium matrix composite with silicon carbide fibers (SCS6/Ti-15-3) subjected to thermal cycling from 149°C to 427°C and 149°C to 649°C were investigated. The degradation of the reaction zone was the first sign of damage due to thermal cycling. It initiated at 500 cycles and continued to grow with increase of thermal cycles. The Young's modulus, Poisson's ratio and residual tensile strength did not change due to thermal cycling up to 15,000 cycles for both temperature ranges. However, the observed internal damage as the degradation of the reaction zone manifested in the form of linear stress-strain response during residual tensile test. A simplified micromechanics analysis was also conducted to assess the state of stress to interpret the experimentally observed response of the tested metal matrix composite.

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References

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