Titanium boride (TiB) is intentionally added to the melt for grain refinement to improve mechanical properties.
Phosphorus is added to the melt hypereutectic alloys for modification of the silicon phase for better mechanical properties. This creates AlP inclusions.
Boron treatment inclusions ( (Ti, V)B ) form when boron is added to the melt to increase conductivity by precipitating vanadium and titanium.