Failure Analysis of Epoxy Resin Encapsulant During a Long-Term Storage
The crosslinked epoxy resin encapsulant protecting an electromagnetic valve coil failed during long-term storage and was examined to determine the cause. The investigation included fault-tree analysis, FTIR and EDX spectroscopy, and differential scanning calorimetry with thermogravimetric analysis. Based on test data, the epoxy resin had not been properly cured and was hydrolyzed in its compromised state because of humidity. Hence, the depolymerized material gradually softened to the point where the effect of creep caused it to flow, ultimately causing the failure.
Guobin Zhang, Yusen Wang, Shinian Zhang, Chunhe Liu, Failure Analysis of Epoxy Resin Encapsulant During a Long-Term Storage, Handbook of Case Histories in Failure Analysis, Vol 3, Edited By Larry Berardinis, ASM International, 2019, p 326–330, https://doi.org/10.31399/asm.fach.v03.c9001798
Download citation file: