| 摘要 |
PURPOSE:To obtain efficiently a hardened layer of high quality by immersing a minute member made of carbon steel or the like in water or other cooling medium except the part to be irradiated with laser, and irradiating the part with laser. CONSTITUTION:A minute member 1 made of carbon steel or the like is supported with a holder 4, and the member 1 is immersed in a cooling medium 5 except the surface part to be irradiated with laser. A shielding gas is fed from the same direction as the irradiation direction, and the surface of the member 1 is irradiated with laser light of such a power density as to cause no melting of the surface. A hardened layer 2' having a martensite structure is obtd., and the range of a heat affected layer 3' is reduced. |
