2000 年 36 巻 11 号 p. 1044-1046
The induction heating inspection is versatile to detect surface defects on square steel billets. Their bright scratches have poorer emissivities than as-rolled skins, which interferes the temperature mapping to spot defects. Authors sprayed powders elecrostatically before heating. The powder coat effectively levels the emissivity all over and has enhanced the accuracy in an on-line inspection.