The Research On The Optimization Preparing Process And Grain Refining Performance Of Al-Ti-B Master Alloy

Since the1960s, Al-Ti-B master alloy have been used to control the grain size of aluminum and it’s alloys. As the quality of Al-Ti-B master alloy constantly improves, it has been widely used in the modern aluminum processing industry. However, the refining performance of Al-Ti-B influenced by the microstructure and the distribution of it’s second phase deeply, different microstructure result various refinements to-Al. This paper focused on the microstructure variation of Al-Ti-B master alloy produced by "Pure-Titanium-Particle" methods under different conditions, the principles of different technological parameter influences the refining performance, the comparison of the microstructure and the refining performance among Al-Ti-B master alloys form laboratory, domestic and import.The main parameters in the preparation process are the reagent adding order, melting superheating temperature and reaction time. The study indicated that:1.the best parameters combination is reagent mixed-adding, melt superheating temperature between860℃-880℃and30mins reaction time;2. The melt superheating temperature is the determinant factor to the morphology and size of the TiAl3;3. TiAl3changes from block to rods at900℃and all into rods or needle-like above950℃. The modification refinement experiment reveal that:1. adding temperature between720-750℃and amount of0.2%, holding time between3-5mins is the best parameters;2. Al-Ti-B master alloy has a better refining effect when the block TiAl3and fine TiB2are well-distributed in the matrix;3. To industrial pure aluminum and6063aluminum alloy, the refining effect of Al-Ti-B master alloy made in laboratory is better than the domestic product, but not as good as the product from KBM.