| 摘要 |
PURPOSE:To simply and uniformly execute quenching to curving surface in the wide range without melting the center part by forming the laser beam to to an output mode having doughnut shape and irradiating the curving surface with the laser beam while matching this center with the center of the curving surface having the curvature. CONSTITUTION:A material 5 to be worked is irradiated with the laser beam 2 from a laser beam oscillator 1 through a bent mirror 11 and working lens 4, to execute the quenching to the curving surface having the curvature. In the above laser beam quenching method, as the above bent mirror 11, the mirror having the doughnut shape is used and the laser beam at the center part of the laser beam 2 is removed. By this method, after the laser beam 2 passes through the bent mirror 11, the laser beam 2a having the doughnut shaped output characteristic is obtd. By this irradiation of this laser beam 2a, the center part 6 of the quenching does not receive the irradiation and therefore, does not melt. On the other hand, the circumferential part receives the irradiation of the laser beam 2a to form the quench-hardened part 7. Further, to the quenched center part 6, the quenching is executed with transfer of the circumferential quenching heat, and the uniform quenching layer is obtd. in the wide range. |
