温度和应变率对低银无铅焊料力学行为的影响

在不同工况下,采用电子万能材料试验机和分离式霍普金森压杆装置(SHPB)对低银无铅焊料Sn0.3Ag0.7Cu分别进行准静态和动态实验,分析了应变率和温度对Sn0.3Ag0.7Cu动态力学性能的影响。结果表明:低银焊料Sn0.3Ag0.7Cu的应力-应变曲线具有温度软化效应与应变率硬化效应。在不同的温度范围内,应变率硬化效应与温度软化效应对低银焊料Sn0.3Ag0.7Cu的塑性变形的影响是不同的。基于Johnson-Cook模型对实验数据进行拟合、修正得到低温和中高温下Sn0.3Ag0.7Cu的动态本构关系,并且与实验数据进行比较,两者在材料的塑性平台区表现出高度的一致性。

Effect of Temperature and Strain Rate on Dynamic Mechanical Properties of Low Silver Lead-Free Solder

The mechanical properties of low silver lead-free solder Sn0.3Ag0.7Cu were characterized by an electronic universal material testing system and Split Hopkinson Pressure Bar (SHPB) under different working conditions. The influence of strain rate and temperature on the dynamic performance was analyzed. The results show that the stress-strain curves of low silver solder Sn0.3Ag0.7Cu are influenced by temperature softening and strain rate hardening effects. In different temperature ranges, strain rate hardening and temperature softening effects on the plastic deformation of low silver solder Sn0.3Ag0.7Cu are different. The dynamic constitutive relationship was determined through these experiments based on Johnson-Cook model. In the plastic flat phase of Sn0.3Ag0.7Cu, the dynamic constitutive relationship and experimental data have a good agreement