Reversible α⇌ sialon transformation in heat-treated sialon ceramics
Reversible α⇌ sialon transformation in heat-treated sialon ceramics
复制标题
热处理赛隆陶瓷中的可逆 α⇌ 赛隆转变
DOI：
10.1016/0955-2219(93)90074-2
复制
发表时间：
1993
影响因子：
5.7
通讯作者：
T. Ekström
中科院分区：
文献类型：
--
作者：
H. Mandal;D. Thompson;T. Ekström
典型的β-sialon和混合的α-β-sialon起始组合物已经通过无压烧结使用Ln 2 O3或Ln 2 O3 + Y2 O3的等摩尔混合物（其中Ln = Sm，Dy，Yb）来致密化。将所得材料在1000-1500°C下热处理以使晶界玻璃失透成结晶氮氧化物相。研究了稀土离子尺寸和热处理温度对非晶相稳定性、显微组织和力学性能的影响。在这些系统中形成的α-sialon相的微观结构表征表明，α仅在高温下稳定，并在较低温度下转变为β-sialon加晶界相;这为控制最终材料的机械性能提供了一种极好的机制。
Typical β-sialon and mixed α-β-sialon starting compositions have been densified by pressureless sintering using either Ln2O3or equimolar mixtures of Ln2O3+ Y2O3where Ln = Sm, Dy, Yb. The resulting materials were heat treated at 1000–1500°C to devitrify the grain boundary glass into crystalline oxynitride phases. The effects of rare earth ionic size and heat-treatment temperature on the stability of devitrified phases, microstructure and mechanical properties have been studied. Microstructural characterisation of the α-sialon phase formed in these systems revealed that α is only stable at high temperatures and transforms to β-sialon plus grain boundary phases at lower temperatures; this provides an excellent mechanism for controlling the mechanical properties of the final material.