Effect of Melt Temperature on the Effectiveness of the Grain Refining in Al-Si Castings

Figure 7

Morphology of α-Al as a function of the added grain refiner: (a) no melt treatment, (b) localization of (Al,Si)₃Ti phase particles within the α-Al dendrites in the A356.2 alloy treated with 0.3%Ti and poured at 750°C, and (c) 0.1%Ti, 200 ppm B. Note the rosette morphology of the α-Al dendrites (open arrows). (d) 0.1%B.

(a)

(b)

(c)

(d)