Production of in situ aluminum–titanium diboride master alloy formed by slag–metal reaction

Abstract Al–TiB 2 master alloys have received much attention in recent years owing to their potential as efficient grain refiners for aluminum foundry alloys. In this study, the process of production of master alloys was investigated to develop a low cost method, namely, slag–metal reaction. This method can be used to fabricate Al–TiB 2 master alloy in situ from the TiO 2 –H 3 BO 3 –Na 3 AlF 6 and Al system. Since the price of the raw materials is low and the technology is simple, the processing technique appears to reduce the cost of the master alloy. Because of exothermic reactions, not much energy is needed to melt materials. In this process, Titanium diboride particles were formed in situ through the reactions of TiO 2 , H 3 BO 3 and Na 3 AlF 6 . Results showed that when the aluminum melted, the condensed TiB 2 particles that formed in situ were spherical with an average diameter of 1 μm. Furthermore, these TiB 2 particles were distributed uniformly through the master alloy.