Y2O3对MgAl2O4透明陶瓷光学及力学性能的影响OA

Magnesium aluminate spinel(MgAl2O4)transparent ceramics exhibit superior properties including broad optical transmission range,high mechanical strength,and excellent thermal stability,demonstrating significant application potential in the fields of transparent armor,infrared windows,and fairing.However,the diffusion coefficient of oxygen ions in MgAl2O4 is relatively low,and the sintering densification is difficult.Therefore,sintering aid is often introduced during the sintering process.Rare earth sesquioxides,being resistant to volatilization at high temperature,have been shown to effectively promote the densification of MgAl2O4 ceramics.This study employed commercially available MgAl₂O₄ powder as the raw material and Y2O3 as the sintering aid.The MgAl2O4 transparent ceramics were successfully prepared through a combination of pressureless presintering and hot isostatic pressing(HIP).The microstructure,optical and mechanical properties were systematically characterized and analyzed by scanning electron microscopy(SEM),UV-Vis-NIR spectrophotometry,and universal testing machine.The results indicate that the MgAl2O4 ceramics doped with 0.020%(mass fraction)Y2O3 prepared by pressureless presintering at 1 525℃and HIP at 1 600℃,the prepared sample exhibits optimal transmittance.The transmittance at 550 and 3 000 nm reaches 84.5%and 87.8%,respectively,while the flexural strength reaches 333.2 MPa.Compared with the undoped Y2O3 samples,the average grain size of the MgAl2O4 ceramics doped with 0.020%Y2O3 decrease from 8 µm to 4 µm,and the flexural strength is increase by 9.79%.