Case 2268 ยท Public preview
Excess Gold Can Fill a Solder Joint with Brittle Intermetallic
Soldered metal-clip attachments were evaluated after pull testing and in an assembled comparison.
MicrosectioningSEMEDSMetallographic etchingImage analysisFracture-path comparison
What the evidence preview establishes
Gold-bearing intermetallic exceeded customary embrittlement thresholds and occupied an estimated 14.5% of the bulk solder in one attachment. Fracture followed the copper-to-gold-copper-tin intermetallic interface, making excess gold a credible design-level embrittlement risk.
Why this case matters
Control total gold entering the solder volume, not merely the final finish specification. Quantify gold-bearing intermetallic, map the fracture path, and remove unnecessary gold from the baseline when brittle phases occupy a substantial fraction of the joint.
Full evidence reserved for MEMBER and STOREThe complete case includes the evidence sequence, four interpreted figures, alternative explanations, limitations, and practical application guidance.