| 摘要 |
PURPOSE:To cut so as to minimize the sticking of a dross onto a material by specifying the injection pressure of an assist gas and setting the focal position of a laser beam in the space of the back face from the plate thickness center part of a material. CONSTITUTION:The laser beam 1 transferred to a work head 2 is condensed by a work lens 3. An argon gas is simultaneously led into the work head 2 and injected to a work 6 from a nozzle 5. At this time the argon gas covers the laser beam condensing part of a work 6 and shields so that the atmosphere is not mixed in the condensing part. Also, since the argon gas differs from an active gas, causing no reaction with aluminum, a work is melted without forming an alumina compound. Due to the focal position 7 of the laser beam 1 being set between the plate thickness center part 6a and back face 6b of the work 6, the cut face taper is big and the upper part cut width lb becomes wider as well, so the molten aluminum can be removed by blowing it off easily by setting the pressure of the argon gas more than 3kg/cm<2>. |
