Synthesis And Grain Refining Behavior Of New AlTiC Refiners

Grain refinement has been an important technique for improving the soundness of aluminum products for most of this century. The addition of grain refiners is one of the most effective, practical and economic way of grain refining in the industrial production,Al-Ti-C grain refiners are effective. Thus, it is necessary to develop new preparation technics of the master to control its composition and microstructure, especially particle distribution, and to investigate grain refinement mechanism, which are important for production of aluminum alloy and offspring process of aluminum output (such as aluminum foil).In this work, a low cost and high efficient Al-Ti-C master alloy was synthesized by aluminothermal reaction under ultrasonic vibrations. The effects of ultrasonic vibrations on synthesis process and microstructures of the masters were investigated, and the grain refining performance on pure aluminum of the AlTiC masters with two compositions synthesized under ultrasonic vibrations was studied in comparison with that of the commercial masters, i.e., Al5Ti1B/Al3Ti0.15C/Al5Ti0.2C. The effect of Si and Fe contents in pure aluminum on refining effect of Al-Ti-C was systematically investigated. The morphologies of the nucleus in the refined pure aluminum were observed and analyzed, and the invalidation of AlTiC/B during heat preservation for a long time was preliminary study. The results of this work are as follows: Ultrasonic vibrations during Al-Ti-C preparation not only accelerated reaction, but also improved the microstructure of the final product. Demonstrate that Al-Ti-C master has more effective and potential advantages on refining aluminum alloy.