| 摘要 |
PROBLEM TO BE SOLVED: To provide a fatigue crack detection method in which a color development error due to fatigue crack does not occur, and deterioration of visibility due to discoloration does not occur, and has high reliability.SOLUTION: A storage space 25 is formed by a metallic substrate 20 or by the substrate and metallic sealing means, then, a paste-state fluid 11 including metal having hardness equal to or higher than that of the metallic substrate 20 or sealing means, or fine particles of metal oxide, is stored in the storage space 25, then, black colored fine powders which are generated from the substrate 20 or sealing means because of action of flowing of the paste-state fluid 11 from fatigue crack 21 generated on the substrate 20 or sealing means due to progress of the fatigue crack 21, to the fatigue crack 21, pass the fatigue crack 21, exit to outside of the storage space 25, then form a black color mark 22. The black color mark is visually inspected, thereby the fatigue crack 21 generated on a surface of a metallic structure is detected.SELECTED DRAWING: Figure 6 |
