Aluminum Grain Refinement

Titanium-boron is added to aluminum as a grain refiner. The fine particles act as nucleation sites and ensure that many small grains form instead of fewer large ones. This makes the structure finer and improves strength and crack resistance. You add the alloy as a master alloy to the melt and stir well so it distributes evenly. If you use too much, the structure can become over-refined and castability suffers – so stick to the manufacturer's specifications.