Tests for MT materials

There are four essential aspects involved with the proper performance of a wet method magnetic particle testing (MI) system. The item being inspected must be suitably magnetized in terms of magnetic field strength and orientation. The bath solution must be in proper strength and state of cleanliness. The light environment must be properly maintained in providing sufficient UV and visible light levels. The inspector must be thoroughly schooled and capable in performing his/her functions in accepting good items and rejecting bad ones. A downfall in any one of these four areas can destroy the integrity of the MT system. This paper focuses on how properties of wet method MT baths can be monitored to assure that they are in proper working order. Relevant specifications and industry practices are identified and reviewed to highlight this aspect of the MT operation. (author)