Case 1462 ยท Public preview
Cross-Section Evidence Can Preserve Competing Causes of Heater Fracture
A glow plug developed high, unstable resistance, while a new comparison device retained low-resistance continuity through its heater.
Electrical testingOptical microscopyControlled dissectionMicrosectioningSEMEDSControl comparison
What the evidence preview establishes
The heater fractured near the end of its copper sleeve. Sleeve nonconcentricity, degradation, and apparent silver diffusion could produce thermal stress, while the bent tip and a separate inboard crack also supported mechanical bending.
Why this case matters
Preserve both hypotheses when a section shows a thermal-stress concern and external bending. Use dimensional sampling, thermal modeling, diffusion assessment, and load reconstruction to discriminate them.
Full evidence reserved for MEMBER and STOREThe complete case includes the evidence sequence, four interpreted figures, alternative explanations, limitations, and practical application guidance.