【摘要】 以Nb2O5为烧结助剂,通过无压烧结制备氧化铝陶瓷.研究了Nb2O5对氧化铝陶瓷的致密化和显微结构的影响.结果表明,少量的Nb2O5对氧化铝陶瓷的致密化具有明显的促进作用,当Nb2O5的添加量为1%时,可使氧化铝陶瓷在1 500℃获得致密.显微结构上,Nb2O5对氧化铝的晶粒生长也具有显著的促进作用.Nb2O5对致密化和晶粒生长的促进作用主要是通过它在氧化铝晶粒中的固溶来实现的.力学性能测试表明:加入Nb2O5后能够在不影响力学性能的前提下降低烧结温度.更多还原

【Abstract】 Alumina ceramics were prepared by pressureless sintering with the addition of Nb₂O₅.Effect of Nb₂O₅ on the sintering and microstructure of the alumina ceramics was investigated.Results indicate that the densification of the ceraimcs is greatly improved by doping small amount of Nb₂O₅.Maximum density is obtained at 1?500?℃ with a doping level of 1 % Nb₂O₅.The microstructure is characterized by a great promotion of Nb₂O₅ to the grain growth of alumina.The mechanism associated with this process is considered attributable to the dissolution of Nb₂O₅ in alumina grains.The resultant mearsurement of mechanical properties shows that,with the addition of Nb₂O₅,the sintering temperature could be lowered down and meanwhile high bending strength and fracture toughness remains.更多还原