Study On Numerical Simulation And Forming Law Of Laser Circular Scanning Bending Of Laminated Plate

Stainless steel-carbon steel laminated plate is a new kind of resource-saving and cost-effective material.It combines the excellent properties of stainless steel and carbon steel and achieves low-cost applications.Laser bending forming technology is one of the mouldless flexible forming technologies in which the laser energy is used to induce thermal stress and plastic strain in the laminated plate,and then laminated plate is permanently deformed.This technology can solve the problem of small batch production of complex curved parts.In this paper,the kind of stainless steel-carbon steel laminated plate(1Cr18Ni9Ti/Q235A)prepared by the combined technology of explosion and rolling is taken as the research object.A numerical model of laser circular scanning for rectangular metal laminated plate is established.The surface deformation process and the surface deformation characteristics and law under different process parameters are studied.The main contents of this paper are as follows:(1)Establishment of numerical model and analysis of simulation results of laser circular scanning bending of rectangular metal laminated plate.Based on the finite element software of ABAQUS,the numerical analysis model for laser circular scanning bending forming of rectangular metal laminated plate and the heat source model for moving pulse laser were established.During the bending process of the laminated plate,the specific change process of temperature,stress-strain and displacement are obtained.The verification experiment is completed by using the process parameters consistent with the numerical model.The calculation results of the model are consistent with the experimental measurement results.The maximum error value of the centerline bending angle is 4.96%,and the maximum error value of the Z-direction displacement of free end is 5.95%.All errors are within 6%.(2)The analyses of deformation characteristics of laser circular scanning bending forming of rectangular metal laminated plate.Analyzing the bending process of laminated plate and the surface deformation characteristics are obtained according to the simulation results of the established model.The distribution of Z-direction displacement along the scanning line of the plate is large in the middle and small on the both sides,but the Z-direction displacement at free end is small in the middle and large on the both sides.The inner plate of the circular scanning line is convex,and the outer plate of the circular scanning line is concave.Affected by the Z-direction displacement of scanning line and free end,the bending angle along the scanning line is small in the middle and large on the both sides.With the partial internal constraint imposed on the free end of the laminated plate,the warpage along the scanning line increased but decreased at the free end,meanwhile,the uniformity of the bending angle along the scanning line is enhanced.(3)Forming law of laser circular scanning bending forming of rectangular metal laminated plate under different process parameters.The influence of laser parameters:laser power P,laser scanning speed v,defocusing distance H and geometric parameters:radius of laser circular scanning line R,width of laminated plate W,the distance between the apex of scanning line and the free end L_F on the laser circular scanning bending forming of the laminated plate are studied.The laser parameters affect the energy distribution in the heating zone and then affect the thermal stress distribution.The geometric parameters directly affect the thermal stress distribution and the internal stiffness constraint of the laminated plate.Based on the application of laser three-dimensional forming of the laminated plate,the experimental forming work of the grooved parts and the arc-shaped surfaces are completed.In this paper,the characteristics and law of laser circular scanning bending forming of rectangular metal laminated plate are obtained through the method of numerical simulation.It is of great significance in guiding the laser bending forming of grooved parts.