Effective acquisition of the related mechanical properties of lead-free solder alloys through micro-indentation tests is of great significance in the research on electronic interconnection design and reliability for the multi-functionalization and high integration of electronic products. The temperature-dependent elastoplastic and creep parameters of Sn–3.0Ag–0.5Cu (SAC) solder are systematically investigated by micro-indentation with plural indenters and the “rapid loading-holding-rapid unloading” test mode. Based on the depth dependence of indentation hardness from mechanism-based strain gradient plasticity and the stress independence of creep compliance for linear viscous assumption, the complete indentation load-depth curves eliminating the indentation size effect of SAC solder under different temperature and two pyramidal indenters with different equivalent semi-cone angles are reconstructed. Combining with the temperature-dependent elastic modulus measurements from cylindrical indentation, corrected load-depth curves for pyramidal indentation, and the concept of representative stress and representative plastic strain, the elastoplastic parameters eliminating the indentation size effect under different temperature are uniquely determined through numerical simulation and inversion analysis, as well as the corresponding creep parameters. The temperature dependence of elastoplastic and creep parameters of SAC solder is analyzed, and related deformation mechanism is discussed. Results of forward and inverse analyses indicate the effectiveness of proposed characterization method.

通过微压痕测试有效获取无铅焊料合金的相关力学性能，对于电子产品多功能化、高集成化的电子互连设计及可靠性研究具有重要意义。通过使用多个压头的微压痕和“快速加载-保持-快速卸载”测试模式系统地研究了 Sn-3.0Ag-0.5Cu (SAC) 焊料的温度相关弹塑性和蠕变参数。基于基于机制的应变梯度塑性压痕硬度的深度依赖性和线性粘性假设蠕变柔量的应力无关性，重建了完全的压痕载荷-深度曲线，消除了不同温度下SAC焊料的压痕尺寸效应和具有不同等效半锥角的两个锥形压头。结合圆柱压痕随温度变化的弹性模量测量值、锥形压痕修正的载荷-深度曲线以及代表性应力和代表性塑性应变的概念，通过数值模拟唯一确定了消除不同温度下压痕尺寸效应的弹塑性参数和反演分析，以及相应的蠕变参数。分析了SAC焊料弹塑性和蠕变参数的温度依赖性，并讨论了相关变形机制。