Addition of AlTi alloy refiners into an Al melt induces grain refinement of ¡-Al grains in as-cast pure Al. In this study, the effects of cold rolling for the AlTi alloy refiners on the grain refinement of as-cast pure Al were investigated. The Al 3 Ti particles in the refiners, which act as nuclei for the ¡-Al grains, were fragmented by cold rolling. Grain size of the ¡-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 Al 3 Ti 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.

Grain refining experiments for casting of pure Al were conducted to evaluate the grain refinement performance of an Al-5mass%Ti alloy refiner before and after cold rolling. Al3Ti particles in the Al-Ti alloy refiner were efficiently fragmented by cold rolling. The size of the Al3Ti particles in cold rolled Al-Ti alloy refiner decreased from 280μm to 30μm with increasing reduction ratio of cold rolling. Mean size of α-Al grains in pure Al cast refined by the cold rolled Al-Ti alloy refiner decreased from about 500μm to 200μm with increasing the reduction ratio. In order to investigate mechanical property of the pure Al cast refined by the cold rolled Al-Ti alloy refiner, Vickers hardness test and tensile test were conducted. Strength of the pure Al cast refined by the cold rolled Al-Ti alloy refiner increased with increasing the reduction ratio. The strength improvement of pure Al cast refined by the cold rolled Al-Ti alloy refiner followed Hall-Petch relationship. From obtained results, it was concluded that cold rolling for refiner is useful practical application for pure Al cast.