The cutting of thick steel plate using a spinning Nd:YAG laser beam

Abstract

Listen

Translate article

Commercial industrial lasers typically cut mild steels up to 15mm thick, producing cut surfaces requiring no or minimal post machining. There is industry interest in increasing this thickness because of the benefits lasers offer compared to other thermal cutting technologies due to improved part accuracy and lower part distortion. One approach to increasing the cut thickness involves manipulation of the beam and focal spot characteristics A program of work has been initiated to investigate cutting mild steel plate up to 25mm thick using “spinning” laser beam technology. Reported here are preliminary results of mild steel cutting trials using both conventional and “spinning” optics with a CW 2.5 kW Nd:YAG laser delivered through a 0.6mm diameter silica core optical fibre. The samples range in thickness from 10 to 20 mm.Results to date show that for the spinning beam, there is a significant increase in the thickness of material that can be cut for a given laser power. However when compared to conventional cutting of medium thickness plate (10 and 12mm), there is minimal improvement in cut speed. These results provide useful insights into the mechanism of reactive fusion cutting of thick plate as a result of the substantially increased kerf width and consequently greater amount of material removed during the cutting process.Commercial industrial lasers typically cut mild steels up to 15mm thick, producing cut surfaces requiring no or minimal post machining. There is industry interest in increasing this thickness because of the benefits lasers offer compared to other thermal cutting technologies due to improved part accuracy and lower part distortion. One approach to increasing the cut thickness involves manipulation of the beam and focal spot characteristics A program of work has been initiated to investigate cutting mild steel plate up to 25mm thick using “spinning” laser beam technology. Reported here are preliminary results of mild steel cutting trials using both conventional and “spinning” optics with a CW 2.5 kW Nd:YAG laser delivered through a 0.6mm diameter silica core optical fibre. The samples range in thickness from 10 to 20 mm.Results to date show that for the spinning beam, there is a significant increase in the thickness of material that can be cut for a given laser power. However when compared to conventional c...