This paper describes a microstructure‐based uniaxial strain‐controlled fatigue life prediction model applied to A319 aluminum alloy which is widely used in automobile industry. The materials made with different casting conditions are characterized and quantified in terms of secondary dendrite arm spacing (SDAS), size, and aspect ratio of eutectic Si particles. Uniaxial low cycle fatigue tests have been performed on four groups of A319 alloy under different casting conditions in which cooling rate and Sr addition are variables. It is shown that the effect of various degrees of microstructure on the fatigue life and fatigue behavior is obvious. The first part of the paper is quantitatively characterizing the microstructure of samples to identify the influence of different casting conditions. With regard to mechanic properties, the tensile properties and fatigue behavior of samples are analyzed combining with microstructure. Finally, a microstructure‐based Manson‐Coffin‐Basquin model is proposed to predict fatigue life of Al‐Si alloy.

中文翻译：

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A319铸造合金组织与疲劳参数的定量关系。

本文介绍了一种应用于汽车行业的A319铝合金的基于微结构的单轴应变控制疲劳寿命预测模型。通过二次枝晶臂间距（SDAS），尺寸和共晶Si颗粒的长径比来表征和量化采用不同铸造条件制成的材料。在不同的铸造条件下，对四组A319合金进行了单轴低循环疲劳试验，其中冷却速率和Sr的添加是变量。结果表明，不同程度的微观组织对疲劳寿命和疲劳行为的影响是明显的。本文的第一部分是对样品的微观结构进行定量表征，以鉴定不同铸造条件的影响。关于机械性能，结合显微组织分析了样品的拉伸性能和疲劳行为。最后，提出了一种基于微观结构的Manson-Coffin-Basquin模型来预测Al-Si合金的疲劳寿命。