Method of suppressing extension of fatigue crack, method if detecting fatique crack and paste used for the methods

摘要

A method of detecting fatigue crack by which the fatigue crack can be easily detected by visual observation even in a relatively early stage, and a method of restraining propagation thereof. The detection method includes the steps of: (a) preparing a paste in which particles having hardness not less than that of a base material and an oil having viscosity are mixed with each other; (b) applying the paste to a desired portion of the base material; and (c) detecting fatigue crack based on a change in color generated by movement of base material powder to a surface of the paste, and the base material powder is produced when the particles grind the base material due to opening and closing of the fatigue crack in the base material.