CARBURIZATION HARDENING METHOD AND DRIVING POWER TRANSMISSION MEMBER SUBJECTED TO CARBURIZATION HARDENING

摘要

PURPOSE:To provide a carburization hardening method by which a carbon steel having an austenite crystal grain size of =#10 is obtainable even in the non-sintered articles of a blank material consisting of a low-carbon steel. CONSTITUTION:The blank material consisting of the low-carbon steel is heated to its austenitization temp. or above and is subjected to a carburization treatment and is then cooled down to the austenitization temp. or below. The cooled blank material is rapidly heated to the austenitization temp. or above and is in succession subjected to a hardening treatment. The surface carbon concn. at the time of this carburization treatment is set at about the eutectic point. The rapid heating temp. described above is set at a temp. right above the austenitization temp.