VACUUM CARBURIZATION PROCESSING METHOD, AND METHOD FOR MANUFACTURING CARBURIZED COMPONENT

• Main Authors: NAKATANI TAKAYUKI, IMATAKA HIDEKI, TOUDOU SHOUJI
• Format: Patent
• Language: Chinese; English
• Published: 30.10.2020
• Subjects: CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY IONIMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; METALLURGY; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THESURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION

In the vacuum carburization processing method according to the present embodiment, when a flow of a carburizing gas, which has been calculated on the basis of a diffusion flux of carbon in a surface layer of a steel material, which is obtained in a diffusion simulation using a diffusion equation, is defined as a theoretical carburizing gas flow (FT), and when the time required for an actual carburizing gas flow to become equal to the theoretical carburizing gas flow after commencement of a carburizing step is defined as an intersection time te, the time from the commencement of the carburizingstep until the completion thereof is defined as a carburization time ta, and one-fifth of the carburization time is defined as a reference time ta/5, an early carburizing step (S1) from the commencement of the carburizing step to the intersection time te is performed wherein an actual carburizing gas flow (FR) is set to be equal to or greater than a theoretical carburizing gas flow (FT(te)) at the point where the referen