添加泡沫Cu对PbSnAg/Cu接头热阻及强度的影响  

Effect of Cu Foam on the Thermal Resistance and Strength of As-soldered Pb5Sn2.5Ag/Cu Joints

作　　者：刘桂源 孙凤莲[1] LIU Gui-yuan;SUN Feng-lian(School of Material Science and Engineering, Harbin University of Science and Technology, Harbin 150040,China)

机构地区：[1]哈尔滨理工大学材料科学与工程学院,哈尔滨150040

出　　处：《哈尔滨理工大学学报》2021年第3期127-133,共7页Journal of Harbin University of Science and Technology

基　　金：国家自然科学基金(51174069).

摘　　要：功率电子元件的服役温度远高于常温,器件产热与散热之间不匹配的现象日益突显。针对这一问题,利用泡沫Cu良好的导热性,采用PbSnAg合金进行填充制成焊材,期望提高现有PbSnAg接头的导热性能。测试复合钎料/Cu接头的热阻,观察微观组织的变化,测试相关力学性能,探究复合钎料接头的断裂机理。研究表明,添加泡沫铜可以提高接头的热导率,有效地降低接头的热阻。PbSnAg合金的组织分别为高铅组织和含有化合物的混合组织,添加泡沫Cu之后组织发生了粗化。界面上生成的化合物是Cu_(3)Sn,并且发现在Cu和Cu_(3)Sn界面化合物之间的界面处存在Pb。添加泡沫Cu使焊缝的剪切强度稍有降低,在断口上可以发现裸露在表面处的化合物。The service temperature of power electronic components is much higher than normal temperature,and the mismatch between heat generation and heat dissipation of devices is becoming increasingly prominent.The good thermal conductivity of foamed Cu is used to fill the welding material with PbSnAg alloy.It is expected to improve the thermal conductivity of existing PbSnAg joints.The study focused on thermal resistance,microstructure and shear strength of the copper foam enhanced Cu/Pb-Sn-Ag/Cu joint.The microstructure of PbSnAg alloy is consists of matrix high lead and the mixed structure of high lead and IMCs(intermetallic compounds).Experimental result shows that the grain of PbSnAg coarsened after the addition of Cu foam.The component of the IMCs at the copper foam and the Cu substrate are Cu_(3)Sn.A layer with high Pb content was found between Cu and Cu_(3)Sn.The shear strength of the solder joint decreases slightly due to the addition of the copper foam,and the Cu_(3)Sn IMCs can be found on the shear fracture.

关 键 词：泡沫Cu PbSnAg钎料 热阻 显微组织 剪切强度 

分 类 号：TG425[金属学及工艺—焊接]