| Mechanical properties of (SiC_w+SiC_p) (15Vol.%) AA2124 hybrid composites subjected to aging treatment were studied. The hybrid composites with different SiC_w : SiC_p ratios of 1 : 1, 1 : 2, and 1 : 3 were fabricated by powder metallurgy and were solution treated followed by aging treatment at 190℃ from 0 to 48 hours. In order to build a basis for comparison, an identical aging treatment for the monolithic AA2124 alloy was also conducted. The peak aging time for both the hybrid composites and monolithic AA2124 alloy was determined from the measurement of matrix hardness. The strength, ductility, and work hardening rate of the hybrid composites were evaluated from the result of tensile stress-strain curves. Accelerated aging occurred in the hybrid composites compared to the monolithic AA2124 alloy and the peak aging time of all the composites showed 3-5 hours. The hybrid composite with SiC_w : SiC_p =1 : 1 showed the highest ultimate tensile strength compared to that of the hybrid composites with SiC_w : SiC_ =1 : 2 and 1 : 3. For the under-aged hybrid composite with SiC_w : SiC_p =1 : 1, the work hardening rate was higher than that of the over-aged hybrid composite. |
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