深冷处理改善Al-Si合金性能及机理研究

Study on Improving Performance of Al-Si Alloy by Deep Cryogenic Treatment and Its Mechanism

在液氮温度(77 K)对A l-S i合金进行了深冷处理,并进行力学性能试验和金相组织分析。结果表明:深冷处理显著改善铝合金的组织和性能。为探讨铝合金的深冷处理机理,建立了相应的理论模型,模型认为,铝合金在深冷处理过程中获得压应力、过饱和点缺陷以及析出沉淀物是改善合金性能的原因。由此模型可解释试验结果。

The Al-Si alloy has been treated at 77 K, the mechanical properties testing and microstructure analysis have been done. The results show that deep cryogenic treatment can dramatically improve the microstructure and properties of Al-Si alloy. A theoretical model is proposed in order to discuss the deep cryogenic treating mechanism of aluminium alloys. The model indicates that it is the reason for improving the performance of the alloy that the press stress and supersaturation point defects are produced, the precipitations are separated out in the aluminium alloys by deep cryogenic treatment. According to the model, the experimental results can be explained.