Space-resolved Spectrometric Measurements of the Cutting Front

The most important factor influencing the maximum cutting speed is the absorbed laser power distribution. As the polarization of the cutting laser beam influences the local absorption, the temperature of the cutting front varies using differently polarized laser beams. To determine the local temperature the emission spectra of cuts with a radially polarized CO2-laser were measured and compared with emission spectra of cuts with a circularly polarized beam. The spectra were used to determine the space resolved temperature by fitting with the Planck black-body radiation in the case of predominantly continuum emission and with the spectral lines of Fe I in the case of spectra dominated by line emission.