This is a microsection of an MLCC as mounted on a PCBA. There is a fracture in the top of the MLCC, which is unusual.
The fracture was clearly associated with some type of damage introduced while the ceramic dielectric was in the “green” state, i.e. prior to firing during fabrication of the multilayered ceramic structure. This type of damage cannot have occurred after firing when the ceramic is no longer deformable as it was as green tape.
It is interesting that this defect escaped any visual and electrical inspections that might have been performed at the factory.
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