Strain Tolerances in Nb3Sn Conductors
Knowledge of strain related effects in Nb3Sn conductors has improved in recent years.1, 2 Early critical current — strain measurements showed variations in strain tolerances among conductors and even for individual ones after different reaction heat treatments. It was soon recognized that relative thermal contractions of the constituent materials in conductors combined to place a residual compressive strain on the Nb3Sn compound. Other work demonstrated that whenever Nb3Sn was strained in compression or tension, the critical current, Ic, decreased. Strain-induced critical current changes are now commonly interpreted as consequences of changes in the internal strain state of a conductor and variations from one conductor to another are attributed to differences in individual residual strain states.
KeywordsFatigue Epoxy Posite
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