非化学配比对Mg_(1-3χ)Al_(2-2χ)O_4尖晶石透明陶瓷显微结构的影响(英文)

Influence of Off-stoichiometry on Microstructures of Mg_(1-3χ)Al_(2-2χ)O_4 Transparent Spinel Ceramics

本研究通过真空烧结和热等静压两步烧结制备了一系列的镁铝尖晶石透明陶瓷。我们利用XRD对粉体和陶瓷的物相成分进行了实验分析,并发现配比为0≤χ≤0.20的Mg(1-3χ)Al(2-2χ)O4粉体具有单一的尖晶石成分。SEM观察发现陶瓷主晶相边界上有利于增韧陶瓷的氧化铝晶粒。通过氧化铝颗粒的透过率和增韧效果的综合考虑,在较小的光损失条件下,采用配比χ为1.4的Mg(1-3χ)Al(2-2χ)O4粉体制备的陶瓷的显微结构将会最有利于陶瓷的强韧化。

A series of transparent spinel ceramics were prepared by a two-step sintering process,vacuum sintering followed by hot isostatic pressing. Phase analysis of the powders and the ceramics were performed by X-ray Diffraction （XRD）. The calcined Mg（1-3χ）Al（2-2χ）O4 powders with 0≤χ≤0.20 are mono-phased spinel structure. SEM images show that corundum grains deposited on the main grain boundaries,which are beneficial for toughening the ceramics. Taking consideration of transparency and toughening effect of corundum,the microstructure of the ceramic prepared using Mg（1-3χ）Al（2-2χ）O4 powder with χ of 0.14 is expected better for toughening and strengthening ceramic at less expense of transmittance.