Failure analyses of nonceramic insulators: part II - the brittle fracture model and failure prevention

In this work, an improved version of a brittle fracture model, based on the formation of nitric acid in service through corona discharges, ozone, and moisture, is presented and is used to explain several different modes of brittle fracture. Similar to Part I, we refer throughout this article to the insulators as nonceramic insulators (NCIs). To prevent brittle fracture in-service, its causes must be first established. To prevent brittle fracture in-service, its causes must be first established.

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