Deformation behavior of a PM Al6013/15SiC_Pcomposite sheet at elevated temperature

The elevated temperature deformation behavior of an Al6013/15SiCPcomposite sheet was investigated by uniaxial tensile tests at temperatures ranging from 723 to 853 K and at initial strain rates between 1.67×10-3and 1.67×100 s-1. The strain rate sensitivity exponent was found to be approximately 0.17 which was apparently below that of a superplastic material. A maximum elongation of ~177% was obtained at an initial strain rate of 6.67×10-1s-1and at a temperature of 773 K. The apparent activation energy was calculated to be approximately 370 kJ/mole which is much higher than that of its unreinforced counterpart. The fracture surface morphology showed a large amount of localized plastic deformation in the aluminum matrix and numerous large cavities. The experimental results were compared with that of a high-strain-rate superplastic Al6061/20SiCW. It was considered that premature failure at the reinforcement/matrix interfaces was the main reason for the Al6013 composite not showing superplastic properties.