添加La_2O_3的AlN陶瓷的高压低温烧结

High pressure and low-temperature sintering of AlN ceramics with La_2O_3 as a sintering aid

利用国产六面顶压机在5.0GPa,1300-1800℃条件下实现了以La2O3为助剂的AlN陶瓷体的高压低温烧结。用XRD、SEM、微区拉曼光谱对AlN高压烧结体进行了表征。研究表明,高压制备陶瓷体材料能够有效降低烧结温度和缩短烧结时间,烧结温度最低温度达到1300℃,可比传统烧结方法降低300℃以上,AlN高压烧结体的晶格常数比粉体的减小0.09%左右,其内部存在残余压应力,但AlN六方相的对称性没有发生改变。

Aluminum nitride ceramics with La203 as a sintering aid were fabricated under high pressure（5.0GPa） at a low temperature（1300-1800℃） in a cubic anvil high-pressure and high-temperature apparatus（China type）. The characterization of the sintered bodies was determined by XRD, SEM and Micro-Raman spectroscopy. The results showed the method could lower the sintering temperature and shorten the sintering time effectively. Under high pressure of 5.0GPa, the lowest sintering temperature was 1300℃, which was above 300℃ lower than that for conventional liquid-phase sintering. The lattice parameters of the specimens sintered at high pressure were found to decrease by about 0.09 % than that of the A1N powder and residual compressive stress was found, while hexagonal lattice of A1N was not changed.