Case 1749 ยท Public preview
A Sound Solder Joint Can Pull Away Defective Pin Base Metal
Wire solder joints separated from connector pins during post-solder cleaning, creating the appearance of a solder or plating failure.
Optical microscopySEMEDSMicrosectioningMetallographic etchingAlloy and plating comparison
What the evidence preview establishes
The joints separated because the Kovar pin base metal ruptured beneath the nickel plating. Circumferential strings of voids, included material, and disturbed metal formed a weak subsurface region that predated soldering and plating.
Why this case matters
When a solder joint appears to slip off a terminal, identify both mating fracture surfaces before blaming solder or plating. Intact plating attached to a thin annulus of base metal is strong evidence of a pre-existing subsurface pin defect.
Full evidence reserved for MEMBER and STOREThe complete case includes the evidence sequence, four interpreted figures, alternative explanations, limitations, and practical application guidance.