Nondestructive Testing of the PPMS-9 Dewar Vessel Using a Mass Spectrometric Method

This paper describes the process of nondestructive testing of a Dewar vessel in a cryogenic setup for studying the physical characteristics of PPMS-9 materials using a mass spectrometric method. The methodology enabled the detection and localization of a leak, as well as an estimation of its size, which was approximated to be that of a circular hole with a diameter of approximately 0.6 microns. Following the application of Stycast epoxy adhesive to repair the defect, the evaporation rate of liquid helium was normalized.