Determination of the geometry of laser-cutting fronts with high spatial and temporal resolution

The melt flow velocity and the local surface angles of the cutting front during laser fusion cutting of 10 mm AISI 304 were determined for a laser power of 8 kW and a feed rate of 2 m/min. The cut front was recorded with a polarization goniometer, which uses the polarization of the process emission to determine the local surface angles, allowing to calculate the orientation of the normal vector of the surface. The records in this work were carried out with a frame rate of 75 kHz and a spatial resolution of about 30 lam. This allowed to identify big and small structures moving down the cutting front and to determine their velocities. The approximate velocity of the small structures was 9.1 m/s and for the big structures approx. 2.5 m/s. The information of a usual high-speed video was compared with the additionally obtained geometry information.

Automated summary

In this study, the melt flow velocity and local surface angles of the cutting front during laser fusion cutting of 10 mm AISI 304 were determined using a polarization goniometer. Different structures moving along the cutting front were identified, with small structures having an approximate velocity of 9.1 m/s and big structures around 2.5 m/s. This information was compared with data obtained from a usual high-speed video.