| 摘要 |
PROBLEM TO BE SOLVED: To provide a surface treatment method for a steel material having excellent wear resistance and heat resistance by forming a nitrogen compound layer consisting mainly of a chromium nitride having high adhesion on the surface of the steel material. SOLUTION: In the surface treatment method for a steel material which immerses the steel into a molten salt, an inert gas layer for intercepting the liquid face of the molten salt from the atmospheric air is formed in the vicinity of the liquid face of the molten salt, during the immersion of a nitriding steel into a chromium-containing molten salt, and a chromium nitride is formed on the surface layer part. In this way, the reaction between the components in the molten salt with an oxygen component or moisture is substantially prevented, the stabilization of the diffusion components in the molten salt is attained, and a compound layer as a treatment layer having excellent properties can be formed on the surface part of the object to be treated. COPYRIGHT: (C)2010,JPO&INPIT |
