SnAgCu-nano Al钎料Anand本构关系及焊点可靠性

Anand Constitutive Relation of SnAgCu-nano Al and the Reliability of Solder Joints

研究了含纳米0.1 wt.%Al颗粒Sn Ag Cu无铅钎料Anand本构关系,将本构关系应用于有限元模拟,分析FCBGA器件Sn Ag Cu-nano Al焊点的应力-应变响应。结果表明,在不同的温度和应变速率的条件下,可以采用非线性数据拟合方法得到Sn Ag Cu-nano Al钎料的Anand本构方程的9个参数值。结合Anand本构模型,采用有限元法计算焊点应力-应变,发现FCBGA器件Sn Ag Cu-nano Al焊点应力-应变分布和焊点阵列有明显的关系,最大的应力-应变集中于拐角焊点;Sn Ag Cu-nano Al焊点的应力-应变值明显低于Sn Ag Cu焊点,证明纳米Al可以提高Sn Ag Cu焊点的可靠性。

In this paper, the constitutive relation of SnAgCu-nano Al is investigated and the constitutive model is used in the finite element simulation to analyze the stress-strain response in FCBGA devices. The results show that the nine parameters of the Anand model can be fitted based on nonlinear data fitting method with different temperature and strain rate. Combining Anand model, the stress-strain response of solder joints is calculated by using the finite element method, and it is found that the distribution of stress-strain of solder joints in FCBGA device can be affected by the solder joints array, i.e., the maximum stress-strain concentrates in the concern solder joints. The results also demonstrate that the stress-strain of SnAgCu-nano Al solder joints is lower than that of SnAgCu solder joints, which implies that the addition of nano Al particles can enhance the reliability of SnAgCu solder joints.