Capture the condition before disturbing it
Photograph the affected region with orientation, scale, part identity, and the stage at which it was discovered. Retain affected, unaffected, and unprocessed comparison samples where available. Use lot and process records to identify common exposures. Avoid peeling layers apart or reheating every suspect part before deciding what examination will preserve the most useful evidence.
Delamination evidence map
| Investigation item | Question | Evidence to retain |
|---|---|---|
| Location | Which layer interface has separated? | Annotated region map and examination images |
| Timing | When was the condition first detectable? | Stage-by-stage handling and inspection history |
| Distribution | Which lots or panel positions are affected? | Sample identity and comparative observations |
| Hypothesis | What result would distinguish a cause? | Controlled experiment and decision criteria |
Identify the interface and history
Map the separation against the regional stackup, support edges, openings, and nearby components. Review storage, handling, lamination, assembly, and environmental exposure as separate hypotheses. The moisture workflow is one part of this review, not an automatic diagnosis. Ask a qualified laboratory or responsible supplier which examination can distinguish the competing explanations.
Test a specific corrective hypothesis
Choose a controlled comparison that changes the suspected contributor while retaining relevant construction and loading. Define the observation that would support or weaken the hypothesis. Record interim containment separately from verified corrective action. When a change appears effective, confirm it on the intended build and exposure before rewriting the production requirement or declaring the root cause closed.
Before you release the design
- Preserve the original failed condition before destructive analysis.
- Record all thermal and handling exposures, including rework.
- Compare affected and unaffected parts from relevant groups.
- Track containment, hypothesis testing, and corrective verification separately.
Watch points
- Do not label every blister as a moisture problem without interface evidence.
Practical questions
Should all suspect boards be baked immediately?
Preserve representative evidence first and follow the responsible investigation plan. Reheating can alter the failed condition and may not address the actual mechanism.
Can an improved peel result confirm the cause?
It can support a specific comparison, but only if the tested interface and history represent the failure. Correlate it with examination and the controlled process change.
Technical references
References support the material or design context. Check the exact grade, part number, document revision and project conditions before release.Updated 27 September 2026 · Technical content policy · Engineering guidance supports project review; the agreed drawing defines the build.