Laser Cutting Striation Formation Mechanism

Laser cutting in modern machining has played an increasingly important role. Stripes onthe section have been the effect of laser cutting quality and an important factor restrictingthe development of laser cutting. Stripes on the section are cyclical ups and downsexisting in the laser cutting material. It seriously affects the plane roughness, reducing thecutting quality. On formation mechanism and how to control the stripes on sectionresearch have both theoretical and practical value, and it is necessary.On the background of laser cut stainless steel plate, this paper focus on the theoreticalanalysis and numerical simulation on the flow at the exit of the nozzle flow and cuttinggap, studied the influence of different experimental parameters on the section stripes, andexplore the method to suppress the cutting stripes.First of all, based on the previous research and Analysis on the existing experimentpresented a hypothetical fringes forming, a dynamic model is established for thecorresponding. Secondly, the nozzle outlet airflow numerical simulation, provide the basisfor numerical simulation of the airflow in the slit; obtained through simulation of airflowin the slit structure changes with different gas pressures, and analysis of gas flow velocityand shear stress changing trends. Finally, experiments of cutting stainless steel plate byusing different gas pressure, variation analysis of section stripes. And longitudinal sectionof fringe is divided into two categories; transverse section of fringe is divided into threeareas. And to discuss the two different kind of produce process between first class stripesand second class stripes; Establish and slot corresponding relation airflow structureinstability forms Maher disc longitudinal stripes and transverse section stripes, analysis offormation process of transverse section from the impact of airflow structure fringedirection.