Numerical Simulation And Optimization Of SLA Variable Spot Process Parameters Based On Multi-objective

One of the most problems in additive manufacturing is that the molding process takes too long.In some application scenarios,users hope to ensure the accuracy and mechanical properties of the test piece while the printing time is as short as possible.Obviously,the process strategy that only considers the molding quality cannot meet the needs of users,and the variable spot technology is currently an effective solution.The existing research often focuses on the influence of process parameters on the accuracy or mechanical properties of the specimen.In fact,the process parameters have a coupling effect on the accuracy,strength and forming efficiency of the specimen.Therefore,it is of great practical significance to comprehensively evaluate the three indexes of specimen accuracy,strength and efficiency,and to study the influence of variable spot process parameters on them,so as to obtain the best process parameters.First of all,this paper analyzes the influence of slicing process and photosensitive resin on the quality and forming efficiency of the specimen,and studies the mechanism of light curing forming and the influence of spot size on the forming specimen,which provides a theoretical basis for subsequent experimental research.The principle of variable spot forming and laser scanning system are studied.A new type of variable spot mechanism is designed and precise control is realized.Secondly,a single small spot strategy was used to scan the outer contour and internal filling.The mathematical model was fitted by response surface method and variance analysis.The significance of process parameters on forming error,tensile strength and printing time was compared.On this basis,the coupling relationship between the variable spot process parameters and their interaction on the evaluation index was studied by using the small spot scanning outer contour and the large spot internal filling.The satisfaction function is used to optimize the single objective of the curing process parameters and the results are verified by experiments.Finally,the mathematical model established by the response surface method is combined with the NSGA-II algorithm,and the multi-objective optimization of the variable spot process parameters is carried out by considering the three evaluation indexes of size error,tensile strength and printing time.The optimal Pareto solution set is obtained by calling gamultiobj function with MATLAB software,and three sets of process parameters are randomly selected for verification,which provides guidance and reference for actual printing processing..