Research Of Crack Propagation Of Glass With Laser Induced Thermal-crack Propagation Based On XFEM

Glass has many excellent properties such as: high hardness,high transmittance and light weight,it has been widely used in manufacturing and daily life,especially the displays of portable electronic equipment.Traditional mechanical cutting method needs complicated afterprocessing,and there will be micro cracks and residual stresses at the cross section of the glass.These problems can be avoid by laser induced thermal-crack propagation.Studying on the dynamic propagation process of crack and the influence of cutting parameters on the stress distribution and the deviation of the separation path with laser induced thermal-crack propagation has important theoretical and practical significance to improve cutting quality.Propagation process of crack and the deviation of the separation path in laser asymmetry cutting glass were studied.Firstly,the basic principle of laser induced thermal-crack propagation was discussed from the perspective of the knowledge of heat transfer,thermoelasticity and brittle fracture mechanics,and the way of heat absorbing by glass under different heat source modes was discussed.The finite element method(FEM)model was established by ABAQUS software,the moving laser heat source was programmed by FORTRAN.The temperature field distribution under different heat source model and different cutting parameters were simulated by changing the parameters of the program.And the regular pattern of the influence of cutting parameters on the temperature field and heat flux field were obtained.The model of laser cutting of glass with laser induced thermal-crack propagation was established to simulate the dynamic propagation of crack based on the extended finite element method(XFEM).The mechanism of crack propagation was explored,the stable propagation conditions of crack was proposed.The stress distribution of the surface and interior of the glass in asymmetric cutting was analyzed.Experimental study on the deviation of the separation path in laser asymmetry cutting glass was carried out,The experimental data and the simulation data were analyzed,and the influence of different cutting parameters and different cutting positions on the deviation of the separation path was obtained.In this study,the dynamic propagation process of crack of laser cutting glass with laser induced thermal-crack propagation based on XFEM method were analyzed.The mechanism of crack dynamic propagation was proposed from the analysis of temperature distribution and stress distribution.The influence of different cutting parameters and different cutting positions on the deviation of the separation path was obtained by simulation analysis and experimental study.