Simulation Of Laser Cladding Residual Stress Reduction By Hammering And Research Of Hammering System

The accumulation of residual stress in laser cladding process will lead to cracks and reduce the performance of parts.Therefore,it is of great significance to study the reduction of residual stress in laser cladding.This paper will try to use the hammering method to reduce the residual stress of laser cladding,and focus on the influence of multi-node hammering on the reduction of the residual stress of laser cladding through simulation.At the same time,based on DMC1380 control card and AT89C52 single chip microcomputer,this paper design a follow-up three-axis hammering platform,and verify the simulation results.In this paper,the research background,significance and current status of hammering method for reducing residual stress in laser cladding are introduced,and the research content of this paper is determined.In order to obtain the basic parameters of the cladding layer for simulation,the influence of different process parameters on the width and height of the cladding layer was discussed,and the size of the cladding layer was determined to be 20mm*2 mm*0.6 mm.Then the temperature field and stress field of laser cladding are simulated,and the distribution of residual stress in the cladding layer is obtained,which lays the foundation for the simulation of hammering.In the hammering simulation,the melting channel is divided into 10 parts along the length direction,and hammering is carried out in the center of each area.The effects of four different hammering factors on the residual stress of cladding layer are analyzed.The simulation results provide guidance for the selection of hammering parameters and the design of hammering platform.According to the parameters provided by hammering simulation and the requirements of hammering test,the key components are selected,the follow-up three-axis hammering platform is built,and the basic hammering control software is developed.The platform can set the technological parameters of laser cladding and the cladding trajectory,and realize the hammering force of electromagnetic hammering device and the hammering force of electromagnetic hammering device and frequency control.Finally,the temperature of the molten pool and the residual stress of the cladding layer during laser cladding are measured to support the simulation results.In view of the current laser cladding process in the laboratory,the temperature field and stress field are simulated firstly.On this basis,the influence of multi-point hammering on the stress field is simulated.The influence of impact force and frequency on the stress field is studied.The simulation study lays a good foundation for the subsequent process test and hammer platform design.The follow-up three-axis hammer platform is developed.The simulation results are preliminarily verified by the platform.