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用挤压铸造、挤压比仅为１０∶１的挤压以及进一步的轧制成功地制备了具有高应变速率超塑性行为的βＳｉＣ晶须增强ＬＹ１２复合材料。该复合材料晶粒细小，约为２μｍ；在温度为８０３Ｋ和初始应变速率为１．１×１０－１ｓ－１时，延伸率达３５０％，应变速率敏感系数ｍ值约为０．３５；超塑性变形的主要机制是细小晶粒的晶界滑动，适当的微量液相有利于该复合材料的高应变速率超塑性。
The βSiC whisker-reinforced LY12 composite with high strain rate superplastic behavior was successfully prepared by extrusion casting and extrusion ratio of only 10: 1 and further rolling. The grain size of the composite is as small as 2 μm. The elongation is 350% and the strain rate sensitivity coefficient m is about 0.35 at the temperature of 803K and the initial strain rate of 1.1 × 10-1s-1. The main mechanism of plastic deformation is the sliding of the grain boundaries of fine grains. Appropriate trace liquid phase is favorable for the high strain rate superplasticity of the composites.