Preparation of hollow particle mold flux for continuous casting by spray drying
During the continuous casting process,the copper crystallizer needs to continuously use mold flux materi-als under high temperature conditions to meet the process requirements of heat transfer and lubrication between the solidified steel shell and crystallizer.Continuous casting process has very high requirements for the macroscopic structure,morphology,moisture content and other physical and chemical properties of mold flux.The rotary vis-cometer was used to test the viscosity of mold flux slurries with different water content configurations.The spray drying production line was used to produce slurries of different materials.DSC-TG,SEM,particle size analysis,and spreading property test were used to characterize the structure and properties of the produced mold fluxes,and hollow particle mold flux with better performance and production process parameters were obtained.The results show that,as the amount of water added to the slurry increases from 33.7%to 53.7%(mass fraction),its viscosity decreases from 25.1 Pa·s to 7.6 Pa·s,and its fluidity is enhanced.Different inlet hot air temperature of spray dr-ying can adapt to different range of slurry water content,and it has a greater impact on the residual water content of mold flux.The particle size distribution of mold fluxes is concentrated in 0.16-0.50 mm,of which 0.35-0.45 mm mold flux accounts for more than 55%,with a resting angle of 29°.The mold flux prepared by spray drying method has obvious hollow ball structure,and the concentricity and spreading performance of particles are good.The re-search results have reference significance for the production of mold flux by spray drying method.