采用有限元数值计算方法，对表面组装件的典型结构进行了对流再流焊的瞬态热模拟，以清晰、直观的等温线图描绘了再流焊各阶段温度的分布，可定量地了解表面组装件热传输特性。本方法可用于ＳＭＴ再流焊工艺（温度曲线）的优化和温度曲线的计算机辅助设计，有助于提高ＳＭＴ的成品率与产品的可靠性。 The finite element numerical method was used to simulate the transient thermal simulation of convection reflow soldering on the typical structure of the surface assembly. The temperature distribution in each stage of reflow soldering was depicted clearly and intuitively. The surface structure Assembly thermal transfer characteristics. The method can be used for SMT reflow soldering process (temperature curve) optimization and temperature curve of computer-aided design, contribute to improve SMT yield and product reliability.