Mechanical Properties of (SiC)p/Al Composite Fabricated by Sheath Rolling

Abstract

Aluminum based MMC reinforced with SiC particles was fabricated by the sheath rolling method. A SUS304 stainless steel tube was used as a sheath. A tube was filled with a powder mixture of aluminum and reinforcement, reduced 75% in thickness by rolling at ambient temperature, and then sintered at 560°C for 1.8ks. The composite was thermomechanically treated to improve its mechanical properties. The results of the present study were compared to those of Al 2 O 3 /Al composite fabricated by the same method. A powder compact of which the relative density was above 0.95 was obtained by cold sheath rolling only. After sintering, the tensile strength of the composites increased with increasing volume fraction of SiC, and it reached a maximum of 100 MPa which was 67% higher than that of the unreinforced material. The elongation decreased monotonously with increasing volume fraction of SiC. Both the strength and the elongation for the composite were not improved by thermomechanical treatment. This means that the powder mixture had been consolidated already almost completely by the sheath rolling followed by sintering. The strengthening effect by reinforcement was also recognized at elevated temperatures.