화학공학소재연구정보센터
Journal of the American Ceramic Society, Vol.98, No.10, 3332-3337, 2015
Insights into High-Temperature Uniaxial Compression Deformation Behavior of Ti3AlC2
We report on strain-rate-dependent compression deformation behavior of Ti3AlC2 at 1000 degrees C-1200 degrees C. At 1000 degrees C and high strain rate (10(-2) or 10(-3)s(-1)), Ti3AlC2 deforms in a nonplastic manner. Upon increasing temperature and reducing strain rate, Ti3AlC2 exhibits a limited plasticity. For instance, the true plastic strain at 1200 degrees C and 10(-4)s(-1) is only 3%, beyond which strain softening following a short hardening regime occurs. The softening results from the formation of localized microvoids and microcracks. Decreasing the strain rate further to 10(-5)s(-1) at 1200 degrees C, strain hardening instead of softening is identified. Under such conditions, the plastic strain remarkably increases, reaching a value as high as 27%. Postdeformation microstructural analyses of the dislocation configurations explicitly evidence the dislocation reactions, formation of hexagonal dislocation networks and dislocation entanglements. These account for the strain hardening. The extraordinary plasticity at 1200 degrees C and 10(-5)s(-1) benefits from the initiation of nonbasal slip systems. Finally, a complete high-temperature deformation scenario for nanolaminated Ti3AlC2 is elaborated.