2013 年 38 巻 4 号 p. 667-672
Magnetic particle testing (MT) was performed with microcapsules containing magnetic particles with fluorescent pigment adhering to their surfaces. These particles gradually separated into fluorescent pigments and magnetic particles with time. To apply the particles, emulsions of inner water and oil were made by hand shaking. Then, these emulsions were heated and stirred with the outer water in a beaker. The solvent of the oil phase evaporated as a result. Thus, microcapsules of inner water/oil/outer water were formed. MT was demonstrated using microcapsules containing 6.8 wt% fluorescent pigment magnetic particles. These microcapsules were placed into a crack in the dark and observed using a fiber. In addition, elemental analysis measurements of the surface were made by a coupling device consisting of a composite-type optical fiber, spectroscope, and pulse laser. A pure metal and an alloy were measured. The spectra of the pure metal were identified using the electronic database of the National Institute of Standards and Technology. These spectra were then compared with those of the alloy. This analysis method may be useful for elemental analysis at certain locations, such as narrow areas, where conventional methods cannot be employed.
