微波分离场加热焊锡膏的实验研究

微波加热作为一种快速、高效、清洁的加热方式，在材料处理领域得到了广泛应用。本文结合金属粉末的微波耗散机理，分析了焊锡膏在微波电场及磁场中的加热特性，通过实验研究了焊锡膏电路在微波电场、微波磁场中的加热效果。实验结果表明，微波电场和微波磁场均可快速加热焊锡膏，但高强度的微波电场容易激发等离子体，灼伤基板；而微波磁场则选择性地加热焊锡膏，实现快速加热融化焊点的同时保持基板在较低温度。通过对比微波磁场快速融化的焊点与传统方式加热融化焊点的微观结构，发现微波磁场快速加热融化的焊点具有极薄的金属间化合物厚度，有利于提高焊点强度。该研究为柔性等塑料基电路的焊接提供了一种良好的解决方案。

Experimental study on solder paste welding by microwave separated field

Microwave heating, as a fast, efficient and clean heating method, has been widely used in materials processing. In this work, the heating characteristics of solder paste in microwave electric field and magnetic field are analyzed according to the microwave dissipation mechanism of metal powder, and the heating effect of solder paste circuit in microwave electric field and microwave magnetic field is studied. The experimental results show that both microwave electric field and microwave magnetic field can quickly heat the solder paste, but the high intensity microwave electric field is prone to excite the plasma and burn the substrate. Contrarily, microwave magnetic field selectively heats the solder paste to achieve rapid heating and melting of the solder joint while keeping the substrate at a low temperature. By comparing the microstructure of the solder joints melted by rapid microwave field with those melted by conventional heating, it was found that the solder joints melted by rapid microwave field heating have extremely thin intermetallic compound thickness, which is conducive to improving the strength of the solder joints. This study provides an excellent solution for the further development of solder paste welding of flex circuits.