MgAlON透明陶瓷无压烧结制备及微观结构研究

Pressureless Sintering and Microstructural Densification of MgAlON Transparent Ceramics

Mg Al ON透明陶瓷是一种组分、性能介于γ-Al ON和Mg Al2O4之间的新材料,可用作红外窗口、整流罩及白光LED灯罩等。作者以Mg Al ON粉体为原料,成型后置于碳管炉中,经1830~1930℃无压烧结,制得了Mg Al ON透明陶瓷,并分析了其微观结构与光学性能。结果表明,受烧结温度的影响,陶瓷中出现了几种典型气孔:晶界气孔、晶内气孔及晶界大孔隙。严格控制烧结温度,1870℃烧结20 h的Mg Al ON透明陶瓷具有结构致密、光学性能优异,红外波段最高透过率达80%。

MgAlON transparent ceramics combine the composition and physical properties between those of γ-AlON and MgAl_2O_4, which makes them as promising candidates instead of sapphire for missile domes, window materials, WLED, etc. In this thesis, MgAlON transparent ceramics were prepared by pressureless sintering of single-phase powders at 1830~1930 °C for 20 h in nitrogen atmosphere. The microstructure and optical transmittances of MgAlON transparent ceramics were analyzed. The decrease of the optical transmittances is due to several kinds of residue pores in the samples. The sample sintered at 1870 °C shows high density and optical transmittance of 80% at 2.0~4.0 μm.