| 摘要 |
PURPOSE:To effectively obtain a steel plate with high workability by forming a doughnut shaped crater of the shape that the hole circumference is swelled at the time of making a rolling roll surface to a rough surface with a laser beam. CONSTITUTION:By using a nozzle for laser beam machining, a rolling roll 6 with the diameter 600mum phi is machined with laser dulling of CO2 laser beam being completely pulsed before a condenser lens 3. Air is used as an assist gas and 120ml/min is fed to the same axis with the laser beam from a gas introducing hole 7, on the other hand, an impeller 11 attached to the top end of nozzle is forcibly rotated with a motor 8 through gears 9, 10, then the assist gas of the peripheral part is removed, and the gas pressure is concentrated only on the central part of metal which is molten with the laser beam. |
