关键词: 无铅钎料 波峰焊 Lift-off 三要素法

Abstract:

This paper puts forth the ＂three-factor method＂for the first time to explain the forming mechanism of lift-off. Compared with the traditional ＂Bi-S egregation＂ invalidation mechanism, the＂three-faetor method＂ can explain the causes of lift-off formed or non-formed by all lead-free solders with annd without bismuth. Finally, the restraining countermeasures against lift-off are also given.

Key words: lead-free solders wave soldering lift-off,three-factor method