With the rapid development of microelectronics and nanoelectronics, Moore law has significantly slowed down and More than Moore based system in packaging (SiP) is expected to be more and more important, at least for next one to two decades. Mechanical behaviors of interconnect materials such as solders are critical for yield in processes and reliability in testing and operation. Based on the framework of crystal plastic theory and continuum damage mechanics, an anisotropic constitutive model coupled with damage was developed to describe the deformation behaviors of Sn-rich solder. In the proposed model, the inelastic shear rate function was presented by hyperbolic sinusoidal form and power law form. For the damage evolution law, the total shear strain was chosen as the damage function variable. The proposed model was implemented into the general finite element software ABAQUS by forward Euler integration procedure. Some simulation examples were performed to verify the proposed model by comparing the simulation results with the experiments at uniaxial tensile conditions with SnAgCuSb solder chosen as the Sn-rich solder. The tensile stress-strain curves of the simulation results agreed well with the experiments at small strain under different temperatures and strain rates. The simulated stress-rupture stages showed reasonable accuracy with the experiments under four representative tensile conditions. Different tensile stress-strain curves of single grains with orientation of (0-0-0)°, (0-45-0)°, and (0-90-0)° were obtained under the same loading conditions, with an inverse relationship between the tensile strength and elongation. This relationship was in accordance with a referable literature. All these results indicate that the proposed model can describe the deformation behaviors of SnAgCuSb solder well under the tensile conditions in consideration of the mechanical anisotropy and the damage evolution.

随着微电子和纳米电子的快速发展，摩尔定律已经显着放缓，并且基于摩尔定律的封装系统 (SiP) 预计将越来越重要，至少在未来一到二十年。互连材料（例如焊料）的机械性能对于工艺良率以及测试和操作的可靠性至关重要。基于晶体塑性理论和连续介质损伤力学的框架，建立了与损伤耦合的各向异性本构模型来描述富锡焊料的变形行为。在所提出的模型中，非弹性剪切速率函数以双曲正弦形式和幂律形式表示。对于损伤演化规律，选择总剪切应变作为损伤函数变量。所提出的模型通过正向欧拉积分程序实现到通用有限元软件ABAQUS中。通过将模拟结果与在单轴拉伸条件下选择 SnAgCuSb 焊料作为富锡焊料的实验进行比较，进行了一些模拟示例以验证所提出的模型。模拟结果的拉伸应力-应变曲线与不同温度和应变速率下小应变下的实验吻合良好。模拟的应力断裂阶段在四种代表性拉伸条件下的实验显示出合理的准确性。在相同的加载条件下，获得了取向为（0-0-0）°、（0-45-0）°和（0-90-0）°的单晶粒不同的拉伸应力-应变曲线，反拉伸强度和伸长率之间的关系。这种关系符合可参考文献。所有这些结果表明，考虑到机械各向异性和损伤演变，所提出的模型可以很好地描述 SnAgCuSb 焊料在拉伸条件下的变形行为。