Effect of Mullite Fiber Content on the Properties of Silica Ceramic Cores Prepared by Selective Laser Sintering Combined with Vacuum Infiltration
Silicon dioxide(SiO2)ceramic cores are essential for manufacturing turbine hollow blades because of their low thermal expansion coefficient,low sintering temperature,and excellent acid-base leaching resistance.The traditional process is limited by the use of molds when forming ceramic cores.Some complex structural ceramic cores are even difficult to manufacture,and the production of high-quality complex structural ceramic cores is challenging.In this study,SiO2 ceramic cores were prepared via a combination of selective laser sintering(SLS)and vacuum infiltration(VI)techniques.Mullite fibers were used as the reinforcing phase,the interference of mullite fibers on the sintering process of SiO2 grains and the delamination phenomenon caused by the accumulation between layers were then analysed,and the influence of the mullite fiber content on the properties of the SiO2 ceramic core prepared by SLS-VI was clarified.The comprehensive performance of the ceramic core is the best when the fiber content is 1 wt.%,with a porosity of 31.16%,a flexural strength at room temperature of 15.23 MPa,and a flexural strength at high temperature of 22.91 MPa.
万方数据
维普
