Grain Refinement of Al sub(3)Ti Dispersed Aluminum Matrix Composites by Reaction Centrifugal Mixed-Powder Method

Aluminum matrix composites having dispersoids of Al sub(3)Ti intermetallic compounds can be obtained by reaction centrifugal mixed-powder (ROMP) method. It is reported that Al sub(3)Ti intermetallic compounds act as grain refiners, since the disregistry value between Al sub(3)Ti intermetallic compound phase and Al matrix is smaller than 10%. In terms of lattice registry between Al matrix and Al sub(3)Ti phase, it is expected that the grain structure of Al matrix in Al-Al sub(3)Ti composites becomes more refined than that of centrifugally cast pure Al. In this study, Al-Al sub(3)Ti composites have been cast by the ROMP method. Effects of the Al sub(3)Ti phases around Ti particles formed by reaction between Al and Ti particles during RCMP method on grain refinement behavior of Al matrix have been systematically investigated. Moreover, grain refining performance of Al cast by Al-Ti refiner with grain shaped Ti particles was also studied.