Thermal stress distributions and microstructure in laser cutting of thin Al-Si alloy sheet

In the present study, laser cutting of thin aluminium-silicon alloy sheet is carried out and the temperature and stress fields are predicted using the finite element code. Surface temperature predictions are validated with the thermocouple data. The changes and geometric features of the cut sections are examined through scanning electron microscope, energy dispersive spectroscopy, and x-ray diffraction. It is found that the high conductivity of aluminum-silicon alloy increases the cooling rates and influences the thermal stress field in the cutting section. The striation patterns are formed at the kerf surface and some small dross attachments are observed at the cut edges. (C) 2013 Laser Institute of America.