圆柱形微波多模烧结腔烧结Al_2O_3陶瓷的性能

Microwave sintering of Al_2O_3 ceramic properties research in multi-mode cylindrical microwave sintering resonant cavity

应用微波加热技术进行高纯Al2O3陶瓷烧结是一种理想的选择.本文使用一种新型的圆柱形微波多模烧结腔体进行了Al2O3陶瓷的烧结研究,该设备可在短时间内达到较高的烧结温度,并能实现坯体的整体烧结.分别对纯Al2O3粉体和Al2O3/MgO混合粉体进行了烧结实验,结果表明,添加MgO作为助烧剂烧结得到的陶瓷试样的相对密度高于纯Al2O3粉体烧结得到的陶瓷试样,在1 700℃下保温40 min,其相对密度可以达到理论密度的97.8%,维氏硬度达22.3 HV/GPa.从SEM图中可观察到试样微观结构良好,晶粒大小均匀,致密化程度高.

Microwave sintering is an ideal method to fabricate high property Al2O3 ceramic.In this work,a new type of multi-mode cylindrical microwave sintering resonant cavity,which can obtain higher sinter temperature in a short time and heat the whole sample,was used to sinter Al2O3 ceramic.Pure Al2O3 powder and Al2O3/MgO mixed powder were used respectively.Results showed that addition of MgO powder was benefit for the increase of relative density.While insulation the sample under 1 700 ℃ for 40 min,the relative density can achieve 97.8% of the theory density,the Vickers hardness was 22.3 HV/GPa.It also observed that the crystal structure of microscopic particles in a large,uniform and high degree of density.