高纯镁砂及氧化镁陶瓷研究进展

高纯镁砂是重要的耐高温材料，氧化镁陶瓷则广泛应用于透光材料领域，对两种材料的生产工艺开展研究具有重要理论和实际意义。本文系统地综述了利用菱镁矿、卤水生产高纯氧化镁及镁砂的各种技术，以及氧化镁陶瓷的烧结方法和烧结助剂对烧结过程的影响；介绍了菱镁矿制备高纯镁砂，卤水沉淀法、卤水直接热解法制备高纯氧化镁，以及电熔法制备高纯镁砂等技术。指出了每种生产技术的优缺点及今后的研究与发展方向。介绍了常压烧结、热压烧结、热等静压烧结、放电等离子烧结、微波烧结和真空烧结等氧化镁陶瓷烧结技术及其进展，总结了烧结助剂对烧结过程的影响及其机理，指出氧化镁陶瓷未来的研究关键主要在于对粉体合成技术、致密化烧结技术及烧结助剂的研究。

A review on the production technologies of high-purity magnesia and magnesium oxide ceramics

High-purity magnesia is an important heat-resistant material and magnesium oxide ceramics are widely used in the field of transparent materials. It has great theoretical and practical significance to study the production process of the two materials. Various technologies of producing high-purity magnesia and magnesium from magnesite and brine, sintering methods of magnesium oxide ceramics and the influence of sintering additives on the sintering process are systematically reviewed. The preparation technologies of high-purity magnesia from magnesite, the preparation technologies of high-purity magnesia by brine precipitation method and by direct pyrolysis of brine method and the preparation technologies of high-purity magnesia by electrical fusion method are introduced. The advantages and disadvantages of each production technology and the research and development directions in the future are pointed out. Various sintering methods and research progress of magnesium oxide ceramics are introduced, including conventional sintering, hot pressing sintering, hot isostatic pressing sintering, spark plasma sintering, microwave sintering and vacuum sintering. The influence of sintering additives on the sintering process and the influence mechanism are summarized. The future research emphases of magnesium oxide ceramics such as powder synthesis technology, densification sintering technology and sintering additives are pointed out.