| Hot restoration and strain rate sensitivity of SiC_p(15Vol.%)/AA2024 composites reinforced with different sizes of SiC_p reinforcements (1, 8, 15, 36. and 44 ㎛) were investigated by hot torsion tests. For the composites reinforced with SiC_P of 8, 15, 36, and 44 ㎛ sizes, dynamic recrystallization (DRX) was responsible for the hot-restoration at 320-480℃. Also, for the composite reinforced with SiC_p of 1 ㎛ size, dynamic recrystallization (DRX) was responsible for the hotrestoration at 320-430℃, and dynamic recovery (DRV) was responsible for the hot-restoration at 480℃. The composite reinforced with SiC_p of 1 ㎛ showed the highest strain rate sensitivity (0.361) at 480℃, even though the failure strain (2.36) of the composite reinforced with 1 ㎛ SiC_p was lower than that (3.65) of the composite reinforced with 8 ㎛ SiC_p. These results were discussed in relation to dislocation density and stacking fault in the matrix grain of the composites by transmission electron microscopy (TEM). |
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