Prediction Of Die Roll Height Of Fine Blanking Component Based On BP Artificial Neural Networks

Die-roll,as one of the basic characteristic of blanked parts,will influence the usability of parts directly.Thus,it become a research focus on how to predict and control the die roll size.The main research method of die-roll is based on FEM simulation to analyze the influence factors,mechanism of these factors and strategy of reducing die-roll size.Prediction of die-roll rest on the period of FEM simulation,it is a time consuming and low accurate method.In this thesis,the main research topics are to establish an accurate prediction model for fine blanking die roll height.A simulation method is adopted to substitute experimental one,to obtain die-roll height data in a certain condition and to avoid time,material and financial resources waste.Considering quality and efficiency in designing simulation scheme,a perfect scheme was put forward by DOE.Die-roll height data acquired in the condition of various geometric features and processing parameters by FEM simulation,and die-roll height prediction models established,by using MATLAB,based on BP ANN with geometrical features and processing parameters as inputs,respectively,and on the basis of the former models an integral prediction model was established.It also can obtain the die-roll height of different material yield stress,according to material correction curve.We can make some conclusions after analyzed three prediction model.(1)The results show that in certain cases,die-roll height increases with the increase of the central angle and the thickness of sheet metal,the influence of the arc radius is opposite,and central angle and the thickness of sheet metal has a stable growth area,in the corresponding area as the change of central angle and the thickness of sheet metal,die-roll height change radian leveled off.(2)The influence of process parameters on die-roll height was analyzed based on the established BP ANN prediction model and the results show that: with the increasing of die clearance,the die-roll height will decrease significantly,when the blanking clearance is in a certain region,the increasing of the fillet radius of die will inhibit the increase of die-roll height.Finally,the degree of importance are confirmed about process parameters,die clearance have major influence on the fine blanking process,follows by blanking speed,fillet radius of die,blank-holding force,and counter force,respectively.(3)The integrity prediction model was established and the influence was considered with different materials.