Experimental research on reliability of reflowed through-hole solder joints

An analysis on reliability of through hole solder joints under thermal shock was carried out in this paper. Compared with the traditional wave soldered joints, the response of reflow soldered joints to the thermal fatigue test were studied in non-destructive and destructive ways. Cracks were caused in solder joints by the coefficient of thermal expansion (CTE) mismatch. And the cracking extent in the reflow soldered joints were dissimilar to that in the wave soldered joints due to the difference of solder joint shape. Furthermore, the failure mechanics of solder joints were analyzed thoroughly.