The effects of temperature on Cu pad consumption and intermetallic compound（IMC） growth were investigated under current stressing. The Cu/Sn-3.0Ag-0.5Cu（SAC305）/Cu solder joints were used, with a certain current density of 0.76×104A/cm^2 at 100, 140, 160 and 180 °C. The constitutive equations of cathode Cu pad consumption and anode interface IMC growth are established, respectively, based on the loading time and sample temperature. The cathode Cu pad consumption（δ） increases linearly with the loading time and the consumption rate shows parabolic curve relationships with sample temperature. The anode interface IMC thickness（δ1） increased is linearly with the square root of loading time and the interface IMC growth coefficient shows parabolic curve relationship with sample temperature. The δ and δ1 have different variation laws under current stressing, due to the current facilitating larger amount of IMC formation in the bulk solder.
冷挤压成形内螺纹具有加工效率高、成本低、牙形流线分布合理、螺纹强度高等特点.底孔直径是冷挤压内螺纹加工过程中的关键工艺参数.研究了工件底孔直径对1100铝合金冷挤压内螺纹性能的影响,利用DEFORM-3D有限元软件模拟1100铝合金M12×1.25 mm螺纹孔冷挤压过程,通过分析不同底孔直径的等效应力应变、扭矩及牙高率的变化,探索最佳底孔直径,并进行实验验证.结果表明:在内螺纹冷挤压数值模拟过程中,等效应力与等效应变变化趋势一致,发生在挤压丝锥与铝合金挤压摩擦的工作区域,说明挤压丝锥的结构也是影响内螺纹冷挤压变形的因素.随着底孔直径的增大,加工过程中的扭矩及牙高率都呈降低的趋势,扭矩及牙高率的有限元模拟结果与实际测量结果吻合较好,验证了有限元模拟的正确性与可靠性.综合考虑成形过程的影响,最佳底孔直径为11.45 mm.
