Or using potassium titanofluorides and titanoborides as grain refiners, which react with carbon in the melt forming carbides of titanium and boron which act as nuclei in solidification. Sodium titanafluoride, titanoboride and silicofluoride fluxes may also be used to provide Ti, B, Si alloying although the extent of alloying in this way is limited to a few per cent only.