REFERENCE PIECE USED IN DETECTION OF SCRATCH IN IRON-BASED MATERIAL, AND DETECTION METHOD FOR THE SCRATCH

摘要

PROBLEM TO BE SOLVED: To provide a reference piece that is used for stabilizing detection conditions when scratches such as cracks being developed inside an iron-based material are to be detected by using a magnetic flaw detector and is easily and inexpensively formed, and to provide a scratch detection method using the reference piece.;SOLUTION: The reference piece 1 comprises: a lower plate 3 penetrating and forming a ring hole 4 at the center; and an upper plate 2 superposed in one piece on the lower piece 3 by a junction means such as diffusion junction. The ring hole 4 of the lower plate 3 is tapped on the surface of the iron-based material of a specimen for covering the entire reference piece 1 with magnetic particles, and irradiation by the magnetic flaw detector is made, thus detecting a ring pattern corresponding to the ring hole 4 at the surface side of the upper plate 2. Scratches can be stably detected by satisfying the detection conditions.;COPYRIGHT: (C)2004,JPO