Aluminothermal reaction to prepare Al-Ti-C master alloy

An investigation was carried out on the reaction process and mechanism between K2TiF6, graphite powder and aluminum melt with the common Ti concentration of 5 % similar to 7 % in the grain-refiner AL-Ti-C master alloys and the reaction temperature of 750 similar to 950 degrees C, aiming at understanding their reaction mechanism and putting forward the aluminothermal reduction reaction method to practical use. During experimental investigation, K2TiF6 and graphite wrapped in aluminum foils were introduced into the aluminum melt at 850 degrees C. Samples of alloy and slag were investigated by chemical analysis, XRD examination, SEM observation, and EDS analysis as well. It was found that the reaction was very vigorous at the beginning of the process and then reached a dynamic equilibrium. There were 3 particular reactions during the aluminothermal reaction process. At the beginning stage of the reaction, there emerged the phases of TiC and one type of metastable intermetallic phase TiAl9 as well as TiAl3 in aluminum melt. At the late stage of the reaction, the metastable phase TiAl9 disappeared and another phase of Al4C3 emerged.