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用示差扫描量热分析了Al-Si合金温度处理的熔体结构变化规律及结构变化温度。结果表明,在升温阶段的Al-7%Si亚共晶、Al-12%Si共晶及Al-20%Si过共晶合金的熔体中均存在额外的热效应,范围均在798～850℃之间,额外热效应温度范围与含硅量无关,结构转变焓值随合金的硅含量增加而增加,氢含量不影响结构转变的温度;而在降温过程中仅在Al-20%Si过共晶合金中发现了额外热效应,额外热效应的出现及温度范围取决于降温速度。分析认为,升温阶段的额外热效应体现了Al的熔体结构变化,降温阶段的额外热效应与熔体中的Si-Si原子团簇的行为有关。
The differential scanning calorimetry (DSC) was used to analyze the melt structure and temperature of Al-Si alloy. The results show that there are additional thermal effects in the melt of Al-7% Si hypo-eutectic, Al-12% Si eutectic and Al-20% Si hypereutectic alloys in the heating range, both in the range of 798 ~ 850 ℃ , The additional thermal effect temperature range has nothing to do with the silicon content, the enthalpy of structural transformation increases with the increase of the silicon content of the alloy, and the hydrogen content does not affect the temperature of the structure transformation; while in the cooling process, only the Al-20% Si hypereutectic Additional thermal effects were found in the alloy, and the presence of additional thermal effects and the temperature range depend on the cooling rate. The analysis shows that the additional thermal effect during the warming phase reflects the melt structure of Al and the additional thermal effect during the cooling phase is related to the behavior of the Si-Si atomic clusters in the melt.