Research On The Macro-morphology Of Glass Mold-oriented Laser Cladding And Modeling Of The Temperature Field Of The Molten Pool

In the glass production industry,the cost of glass mold is expensive.At the same time,because the glass mold is utilized in high temperature and oxidize environment for a long time and suffers frequent mechanical impact and extrusion,the surface of the mold often appears defects such as wear,fracture and so on,which leads to the unusable mold.Laser cladding technology has been applied to the surface strengthening and repairing of glass mold because of its strong pertinence,good strengthening effect and high degree of automation.This thesis focus on the technology of laser cladding and the theory and experiment works are conducted to the macro morphology of cladding layer.Based on the ANSYS software,the modeling analysis for temperature distribution of molten pool is done and some results are given.The main works are listed in the follows.(1)In this thesis,nodular cast iron(ISO 1038/JS/500-7)is used as the base material,and ni30 a is selected as the cladding material.Through a series of testing methods such as metallographic analysis,microstructure observation and hardness measurement,the performance of cladding layer under different process parameters is analyzed,which provides a theoretical reference for further optimization of process parameters.(2)Based on the equipment and control system of the laser cladding system,a series of single laser cladding experiments are designed with a group of optimized process parameters.According to the experimental results,the corresponding theoretical analysis is carried out.The results show that it is feasible to use linear regression equation to predict the macro morphology of cladding layer,including the width and height of cladding layer and the penetration of substrate.The width W of the cladding layer is mainly affected by the laser power P,and the scanning rate v of the robot also has a certain impact on it.Although the height H of the cladding layer is also affected by the laser power and the scanning rate,the partial regression coefficient of the two is not much different,which means that the influence degree is not much different.While the penetration of the substrate is mainly affected by the laser power,and the scanning rate is changed and its variation has little effect on the penetration.(3)Based on the thermodynamics analysis,the ANSYS software and the life and death unit method are used for the simulation of the laser cladding experiment.On the basis of not defining the shape of deposition track in advance,the temperature distribution of molten pool is determined by numerical simulation.So the width and height characteristics of cladding can be predicted by parameters such as laser power and scanning rate.The temperature field of the molten pool is analyzed too.