More recently, discontinuously reinforced metal matrix composites (MMC) have attracted considerable attention as a result of the successful development of manufacturing processes to produce composites with reproducible structures and properties. In this investigation an attempt has been made to develop models to study the influence of secondary processing parameters and their interaction effects on micro hardness and fatigue strength of 6061 - Al SiCp composite. The solutionizing time, ageing temperature and ageing time were varied and factorial technique was employed to design the experiments. The specimens were then tested for micro hardness and fatigue strength and models were developed using the test results. Analysis of Variance (ANOVA) method was used to study the main and interaction effects of the process parameters. The adequacy of the developed model has been found to have very high correlation.