Effect of temperature in single phase regime on aging response of (Al-2Cu)/SiC metal matrix composite synthesised using disintegrated melt deposition technique

Abstract

In the present study, an aluminium based metal matrix composite ((Al-2 wt-%Cu)/SiC) was synthesised using an innovative disintegrated melt deposition technique and investigated to determine its microstructural characteristics and the effect of temperature in the single phase regime on the peak aging characteristics. Microstructural characterisation carried out on the as processed composite revealed the presence of a dendritic-equiaxed microstructure, non-interconnected porosity, uniform distribution of SiC particles, and good interfacial integrity. The results of solutionising studies indicated that the peak hardness during solutionising can only be realised if the composite is soaked at a critical solutionising temperature. Further, the results also indicated that the time required to attain peak solutionising hardness at various temperatures in the single phase regime is independent of the solutionising temperatures investigated in this study. The results of the aging studies revealed that the maximum hardness following aging is achieved for the composite solutionised at a critical solutionising temperature and time. The results of heat treatment characterisation were finally rationalised in terms of the changes in the constitutional and microstructural features during the various stages of the heat treatment procedure used in the present study. © 1997 The Institute of Materials.