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综述了环氧树脂基的PCB与无铅化组装的兼容性问题。经过大量试验表明,常规的FR-4基材和双氰胺固化的高Tg基材是不能满足无铅化组装要求的,而采用酚醛固化的中等-Tg的环氧树脂基材是可能成为无铅化组装用基材的。同时,PCB制造过程也起着重要的作用。PCB设计和再(回)流焊的加热梯度也影响着无铅化的性能。
The compatibility of epoxy-based PCB with lead-free assembly is reviewed. After a large number of tests show that conventional FR-4 substrate and dicyandiamide-cured high Tg substrate can not meet the requirements of lead-free assembly, and using phenolic-cured medium-Tg epoxy resin substrate is likely to be no Lead-based assembly with the substrate. At the same time, the PCB manufacturing process also plays an important role. Thermal gradients in PCB design and reflow (back) also affect lead-free performance.