| 摘要 |
<p>A laser piercing method which reduces a machining time prevents thermal runaway and minimizes variance of a machining time. In this method, piercing is started at an initial pulse frequency Po and an initial pulse duty ratio of Qo, and then the pulse frequency and the pulse duty are increased by increments of P and Q, respectively, at predetermined time intervals of T. After a set number of increments or a predetermined time from the start of machining, the increase is stopped and machining is continued till the completion of machining. Accordingly, the machining time can be reduced to 1/3 to 1/5 of the machining time of the prior art, and thermal runaway can be prevented. Variance of the machining time can be reduced, as well. <IMAGE></p> |
