Numerical Analysis And Experimental Investigation Of Quartz Glass Fabricated Using Laser Coaxial Powder Feeding Additive Manufacturing Approach

Quartz glass components have important applications in national defense science and technology,optics,biomedicine,aerospace and other fields.In recent years,additive manufacturing(AM)has attracted much attention in the preparation of quartz glass materials because of its high processing efficiency,short preparation cycle,low cost and good flexibility of structure and materials.However,due to the characteristics of high melting point,low thermal conductivity,high viscosity and high brittleness of quartz glass materials,quartz glass specimens prepared by additive manufacturing technology generally have problems such as low density and poor mechanical properties,which are limited in practical engineering application.This paper aims to explore a new way of combining laser powder feeding technology with quartz glass forming technology,and provide a good development potential for the application of laser powder feeding technology in the manufacture of glass.The main research contents of this paper are as follows:1)Numerical simulation and analysis are carried out on the manufacturing process of laser coaxial powder feeding additive of quartz glass:combined with the thermophysical characteristics of quartz glass,the effects of main process parameters such as laser power and laser walking speed on the temperature field of quartz glass additive are explored;From single-layer single channel,single channel multi-layer,single-layer multi-channel to multi-layer and multi-channel laser additive manufacturing,the parameter optimization combination of different laser power and laser walking speed is obtained,which provides a feasible technical reference for subsequent experiments.2)Taking quartz glass powder as raw material,the experimental research on manufacturing quartz glass by laser coaxial powder feeding additive was carried out:Based on the results of numerical analysis,single-layer and single channel quartz glass was prepared by orthogonal test method,and the key basic process parameters affecting the geometry and forming quality of quartz glass additive layer were explored and studied.Quartz glass samples were prepared by different additive manufacturing processes such as single-layer multi-channel and single channel multi-layer.The effects of laser specific energy,powder distribution density,falling height and scanning spacing on the forming quality of quartz glass were analyzed.The results show that when the laser specific energy is in the range of73.33-122.22J/mm~2,the bulk density of the formed part is between 2.20-2.21g/cm~3,and the porosity is not more than 0.13%.At the same time,the effects of process parameters such as powder distribution density,scanning spacing and falling height on the density of formed parts are also studied.The test results show that these process parameters have little effect on the density of samples,and the porosity is always kept below 0.35%.3)The results show that when the laser energy density is 214.84J/mm~3(corresponding overlap rate is 66.67%),the maximum mechanical strength of the prepared quartz glass sample is 772.38±5.98Mpa,and its thermal conductivity is1.35J/(m·s·℃).The performance of the sample is close to that of the quartz glass prepared by the traditional method.