Abstract
Stress induced dissipative energies were measured at 4.2K for epoxy cracking in a copper epoxy bonding and an epoxy-impregnated superconducting coil with an AE sensor and a newly developed high-resolution energy transducer. The dissipative energies have been correlated to AE energy. The correlation indicated that it is possible to use AE energy to quantify these dissipative energies. The dissipated crack energies in the coil were determined to be -2mJ at the maximum. Difference in AE waveforms associated with cracking and friction was also observed.
