Grain Refinement of As-Cast Pure Al by Cold-Rolled Al–Ti Alloy Refiner

Abstract

Addition of Al–Ti alloy refiners into an Al melt induces grain refinement of α-Al grains in as-cast pure Al. In this study, the effects of cold rolling for the Al–Ti alloy refiners on the grain refinement of as-cast pure Al were investigated. The Al₃Ti particles in the refiners, which act as nuclei for the α-Al grains, were fragmented by cold rolling. Grain size of the α-Al grains is decreased as increasing the reduction ratio of the refiners. This decrease in grain size is due to the increase in the number of Al₃Ti particles in the refiners. The mechanical properties of the as-cast pure Al are also improved as a result of its grain refinement. In particular, the wear properties of the as-cast pure Al were drastically improved. It is concluded that the cold rolling for the refiners is an effective process to enhance its grain refinement ability.