Study on Thixo-Die-Forging of 37vol.%Al/Al₂O₃ Composite in Pseudo-Semi-Solid State

A new procedure, thixo-die-forging of ceramics/metal composite in the pseudo-semi-solid state, has been proposed based on powder metallurgy combining with the semi-solid processing of metal. The cup-shaped parts of Al/Al2O3 composite are processed with thixo-die-forging. By metallographic analysis and performance tests, the results show that microstructures are compact, grains are fine and mechanical properties are excellent. The bend strength and fracture toughness of 37vol.%Al/Al2O3 are about 430-690MPa and 8.5-16.8 MPa•m1/2 respectively. Comparing with those of the reaction in situ and high temperature oxidation procedures, the bend strength increases by 50% and 80%, and fracture toughness increases by 29% and 55%, respectively. The results also show that the processing parameters, such as temperature and pressure have great influences on the properties. Thixo-die-forging in the pseudo-semi-solid state can prepare Al/Al2O3 composite with high performance.