| 摘要 |
PURPOSE:To uniformly heat the surface of a steel material with laser. CONSTITUTION:When the surface of a steel material is irradiated with a laser beam having a prescribed cross-sectional area to heat the irradiated surface, laser as a planar heat source is used to emit a laser beam having a cross-sectional energy distribution obtd. by concentrically synthesizing a circular beam 4 and a columnar beam 1 having a diameter equal to the inside diameter of the circular beam 4 and lower peak energy than the beam 4. |
