Study of the effects of laser cutting processes on S235 structural steel

Laser cutting technology shows advantages in advanced industrial manufacturing processes due to high machining speed and precision to cut complex geometries. Nonetheless, its thermal process is characterized by complex physical mechanisms that alter material properties and the structural response of the cut element subjected to high fatigue loadings. The optimization of laser cutting parameters by cut attempts and the evaluation of the mechanical response by testing is very expensive. A 3D numerical model based on the FE method was developed to investigate the thermal effects due to the laser cutting process on mild steel S235. Due to the complexity of the process, monitored cutting processes and material tests were carried out to calibrate and validate the FE model. More precisely, temperature profiles were observed by thermal camera and thermocouples on specimens cut using different laser cutting parameters. Besides, microstructural observations on the heat affected zone were performed using microscopy and XRD methods. The proposed model was capable to simulate the laser cutting process and its results were in good agreement with the corresponding experiments in terms of temperature distribution, temperature history, and micro‐structures inside the cut specimen.