| 摘要 |
<p>The present invention provides a gear, continuously variable transmission, constant velocity joint, hub, or other steel part superior in surface fatigue strength compared with the past and method of production of the same, that is, provides a carbonitrided induction hardened steel part made of steel comprising a specific composition of chemical ingredients and carbonitrided, then treated by induction hardening, the steel part characterized in that a surface N concentration is 0.1 to 0.8 mass%, a sum of an N concentration and C concentration is 1.0 to 2.0 mass%, an amount of surface residual austenite is less than 15 vol%, a depth of the incompletely hardened layer from the surface is less than 5 µm, and a surface X-ray diffraction half width is 6.0 degrees or more, and a method of production of the same.</p> |
