Interfacial regulation and fracture mechanism of Al-Si/SiC composites infiltrated under super-gravity field

摘要

We reported a novel method to prepare Al-Si/SiC composites infiltrated under super-gravity field without Mg addition. Noted that centrifugal force acted as the main driving force to overcome the penetration resistance, making it feasible to obtain the Al-Si/SiC composite with high relative density (>= 99.3 %). The interfacial reaction between Al and SiC was retarded by Si addition under super-gravity field. Interestingly, the rod-like eutectic Si was detected at Al-SiC interface with semi-continuous distribution, leading to the excellent bending strength (342.6 +/- 1.0 MPa), enhanced thermal conductivity (173 W/m K at 373 K), and relatively low coefficient of thermal expansion (8.90 x 10(-6) K-1 ranged from 323 to 373 K). The interfacial regulation and fracture mechanism were discussed in details.

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