Abstract:
The objective of this research was to study the influence of boron content (0.04, 0.08 and 0.12 wt.%B) and different sequences on refining efficiency and eutectic modification in Al-Si-Mg Cast Alloy. The Al-4%B, Al-4%B-2%Sr and Al-10%Sr master alloys were used for grain refiner and modifier of each casting condition. Grain size analysis was measured using the linear intercept method. The experimental results showed that the Grain size decreased with increasing B content, while eutectic silicon partially modified the acicular silicon into fibrous morphology. The Grain size of α-Al in the as-cast alloy is 3377 and decreases to 1159, 439 and 428 micron in 0.04, 0.08 and 0.12 wt.% B added, respectively. The addition in terms of 2 wt.% of Al-4B-2Sr revealed less refining efficiency than 0.08 wt.%B + 0.04Sr added, while the eutectic Si was fully modified into the fibrous morphology. The different sequence of addition showed significant influence on the grain size of α-Al when compared to their combined addition