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比较了Ａｌ－３％Ｔｉ－３％Ｂ，Ａｌ－５％Ｔｉ－１％Ｂ中间合金对亚共晶Ａｌ－Ｓｉ合金的晶粒细化效果。结果表明，Ａｌ－３％Ｔｉ－３％Ｂ中间合金的细化作用明显优于Ａｌ－５％Ｔｉ－１％Ｂ。主要是Ａｌ－５％Ｔｉ－１％Ｂ中间合金加入熔体中，过量的Ｔｉ在ＴｉＢ２／熔体界面形成三元铝化物，通过包晶反应成为α－Ａｌ的异质晶核，但包晶反应温度的急剧下降是导致晶粒细化能力下降的直接原因；而Ａｌ－３％Ｔｉ－３％Ｂ中间合金加入熔体中，过量的Ｂ在ＴｉＢ２／熔体界面形成富Ｂ层，在冷却过程中，将发生共晶反应，生成大量的α－Ａｌ晶核，达到细化目的。
The grain refinement effect of Al-3% Ti-3% B and Al-5% Ti-1% B master alloy on hypoeutectic Al-Si alloy was compared. The results show that the refinement of Al-3% Ti-3% B master alloy is obviously better than that of Al-5% Ti-1% B. Al-5% Ti-1% B master alloy is mainly added to the melt. Excess Ti forms ternary aluminide at the TiB2 / melt interface and becomes a heterogenous crystal nucleus of α-Al by peritectic reaction, but the peritectic The sharp decrease of the reaction temperature is the direct reason for the decrease of the grain refinement ability. However, the addition of Al-3% Ti-3% B master alloy to the melt, excessive B forms a B-rich layer at the TiB2 / During the process, a eutectic reaction will occur to generate a large amount of α-Al nuclei, to achieve the purpose of refinement.