A Fabrication of microcapsule containing the fluorescent magnetic particle employed as material of advanced inspection technique in heat exchanger tube

Ito, Fuyumi; Nishimura, Akihiko  

Fine magnetic particles having UV fluorescence are commonly used in magnetic crack detection technique. Stress corrosion cracking sometimes happens in nuclear power plants. To apply this technique to maintain the heat exchanger tubes, it is desired that these particles has performance to be collected with ease. To collect these fine magnetic particles from millimeter size crack depth, a chemosynthesis technique to produce the micro capsules successfully produced hundreds micron sized capsules containing the fine magnetic particles. The synthesized micro capsules indicated the collective sensitivity for lines of magnetic force.