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研究了不同过热温度对Ａｌ－Ｓｉ１６％结晶组织的影响，发现当过热温度超过９００℃后，试样中的初晶硅尺寸与数目大量增加，共晶硅的尺寸变小。ＤＳＣ分析表明，一定程度的过热增加了Ａｌ－Ｓｉ１６％的结晶潜热。液态Ｘ射线研究发现，在９００℃以下，Ａｌ－Ｓｉ１６％的平均配位数比相同温度纯铝低，而在９００℃以上，合金的平均配位数要高。１２５０℃温度过热后，合金熔体在液相线上方就已出现与硅晶态相对应的衍射峰。过热温度对结晶行为的影响可用Ａｌ－Ｓｉ１６％熔体中Ａｌ－Ｓｉ原子团在较高过热温度下向Ｓｉ－Ｓｉ原子集团转化的机制来解释。
The effects of different overheating temperatures on the Al-Si 16% crystalline structure were investigated. It was found that when the overheating temperature exceeds 900 ℃, the size and number of primary Si in the sample increase greatly, and the size of the eutectic Si decreases. DSC analysis shows that a certain degree of overheating increases the latent heat of crystallization of Al-Si by 16%. The results of liquid X-ray showed that the average coordination number of Al-Si16% was lower than pure aluminum at the same temperature below 900 ℃, and the average coordination number of alloy was higher than 900 ℃. 1250 ℃ temperature overheating, the alloy melt above the liquidus has appeared with the diffraction peaks corresponding to the crystalline silicon. The effect of superheat temperature on the crystallization behavior can be explained by the mechanism that the Al-Si atomic group in Al-Si16% melt is transformed into the Si-Si atomic group at a higher superheating temperature.