无铅化再流焊接温度曲线的模拟考虑

Simulating Consideration of Temperature Profile for Lead-Free Reflow

随着电子行业引入了无铅化焊料,这对标准的表面贴装工艺技术提出了更高的要求。其中最大的变化发生在再流焊接工艺中,因为无铅化焊膏需要较高的温度和比常规的SnPb焊料严格的工艺控制要求。当PCB通过再流焊接加热炉的时候,以不同的速率对元器件进行加热,这样会导致电路板上面的温度形成梯度。通过早期预知样品的温度梯度,可以使得优化再流炉的设置和热电偶的连接点变得很容易。

The introduction of Pb-free solder into the electronics industry has required changes to the standard surface mount process. The largest changes are in the reflow process, as Pb-free pastes require higher temperatures and tighter process controls than standard SnPb solders. As the PCB passes through reflow, components are heated at different rates, resulting in a temperature gradient over the board. Predicting temperature gradients prior to prototyping makes it easy to optimize oven settings and thermocouple attachment points.