TiO_(2)纳米掺杂对SAC105焊膏喷印流变特性及接头力学性能的影响

Effects of TiO_(2) Nano Doping on Jet Printing Rheological Properties of SAC105 Soldering Paste and Mechanical Properties of Joint

利用不同含量TiO_(2)纳米颗粒掺杂的方法对SAC105焊膏进行改性,利用旋转流变仪、粘度仪等设备研究了改性焊膏的喷印流变特性,利用拉伸机、扫描电镜等设备研究了改性焊膏焊接接头的力学性能和微观结构。结果表明,TiO_(2)纳米颗粒掺杂改性SAC105焊膏焊接接头的剪切强度最高达71.4 MPa,比未掺杂的SAC105接头剪切强度提高65%,归因于TiO_(2)纳米颗粒在焊点中的第二相强化作用。TiO_(2)含量为1%的SAC105锡膏相比未掺杂SAC105锡膏的蠕变柔量曲线中普弹形变区减小约50%。加入1%〜2%含量的TiO_(2)纳米颗粒能在触变系数保持0.73〜0.74基本不变的情况下,将锡膏粘度值从96.2 Pa·s显著调节至120.2 Pa·s,提供了一种喷印锡膏触变系数和粘度耦合调节的新方法。

The SAC 105 solder paste was modified by doping TiO_(2) nanoparticles with different contents.The rheological properties of the modified solder pastes were studied by using rotating rheometer,viscometer and other equipment.The mechanical properties and microstructure of the joints welded with the modified solder pastes were studied by tensile machine and scanning electron microscope.The results show that the shear strength of TiO_(2) nano doping SAC 105 paste welded joints reaches up to 71.4 MPa,which is 65%higher than that of undoped SAC 105 joint.This is attributed to the second phase strengthening of TiO_(2) nanoparticles in the solder joint.The creep elastic deformation area of SAC105 solder paste with 1%TiO2 is about 50%smaller than that of undoped SAC105 solder paste.Adding 1%-2%TiO_(2) nanoparticles can significantly adjust the paste viscosity value from 96.2 Pa·s to 120.2 Pa·s with the thixotropic coefficient of 0.73-0.74 basically unchanged.It provides a new method for coupling regulation of thixotropic coefficient and viscosity of printing paste.