AlON系透明陶瓷粉体瞬时高温活化合成技术研究

AlON transparent ceramics show excellent properties and promise for applications including optical windows and domes to rival sapphire. These applications require AlON powders with superior performances. Rotary technology based on transient high-temperature activation (THA) combines the advantages of continuous run, high efficiency, good consistence in quality and low cost, as developed by Raytheon corporation in 2002. The complicated processes, involving rotary, atmosphere flow and transient activation under high temperature, are hard to control for the fabrication of powders. As one of the most important segment, related research towards THA is not well clarified. Under the current, it is hard to control the morphology, the thermodynamic and the composition uniformity of the powder. The current research of THA technology is classified as the follows. a) The composition design and optimization; b) the thermodynamic, and kinetic mechanisms; c) the uniformity of chemical composition, etc. Under this program, related basic theory and key technology will be disclosed, which will speed up the progress towards large scale fabrication of the powders with low costs, and the application of AlON transparent ceramic materials.

AlON透明陶瓷是一种性能优异的光学窗口材料，可望替代蓝宝石，受到极大关注。原料粉体是限制该类材料制备乃至应用的瓶颈之一。Raytheon公司发明瞬态高温动态合成技术，是国际上唯一实现AlON粉体低成本、高效合成的方法。因涉及高温旋转动、气氛流动、瞬时高温反应等方面，该方法技术难度大、影响粉体合成的因素多而复杂。我们对其关键环节尚不清楚，尤其是作为核心的瞬时高温技术。这种环境下，如何控制粉体形貌及反应热力学？如何控制粉体成分均匀性？这些问题十分关键，但又没有研究报道。本项目拟结合前期研究基础，通过组分优化设计，研究瞬时高温技术合成过程中的微观形貌、成分均匀性控制等问题的机制，为实现AlON粉体的低成本、高效制备及工程应用起到积极推动作用。

AlON透明陶瓷具有优异的力学、光学及热稳定性等，是红外窗口/整流罩、透明装甲的优选材料。本项目主要开展了AlON粉体合成与反应过程相关机理进行了研究，主要包括：（1）组分优化设计与单相尖晶石结构AlON系热稳定区相图的研究；（2）Mg/Li掺杂对AlON系物相演化特征的影响；（3）物相转化的热力学反应机理研究；（4）粉体微观形貌变化规律、形貌控制机理及添加剂对反应动力学的影响研究；（5）原料混合均匀度对反应产物成分均匀性的影响及其物理机制及相关物理模型的建立。（6）粉体烧结致密化机制及高透明的AlON系透明陶瓷，制备等。通过上述工作的开展，揭示物相形成、微观形貌及成分均匀性控制的物理机制，掌握瞬态高温动态反应合成关键技术，获得了高品质AlON系粉体与透明陶瓷。本项目的开展，为AlON系透明陶瓷材料的制备提供了一定的技术参考和理论支持，为实现其在红外窗口、透明装甲等领域的应用方面奠定了良好的基础。