摘要
为利用轻烧氧化镁制备高性能烧结镁砂,以大石桥产破碎至≤0.074 mm的菱镁矿粉为原料,分别于700、800、900和1 000℃保温30 min煅烧获得4种不同活性的轻烧氧化镁,再将不同活性的轻烧氧化镁分别于1 550、1 600、1 650和1 700℃保温3 h进行二步煅烧制备了烧结镁砂,探讨了轻烧氧化镁活性对镁砂烧结性能、物相组成和显微结构的影响。结果表明:高活性轻烧氧化镁具有更高的缺陷能,从而具有更大的烧结驱动力,可以促进Mg O晶体的发育,提高镁砂的烧结性能,但过高的活性会导致镁砂的致密度降低;利用900℃煅烧的轻烧氧化镁经1 700℃保温3 h二步煅烧制备的烧结镁砂的体积密度可以达到3.41 g·cm-3,并且晶粒发育良好,排布均匀、紧密。
This work aims at preparing high quality sintered magnesia using light calcined magnesia. The light calcined magnesia with different activities was prepared by soaking at 700,800,900 and 1 000 ℃ for 30 min,using ≤0. 074 mm magnesite from Dashiqiao as the raw material. Then,the sintered magnesia was obtained by two steps calcination of the light calcined magnesia at different temperatures（1 550,1 600,1 650 and 1 700 ℃） for 3 h. The effects of light calcined magnesia activity on sintering properties,phase composition,microstructure on sintered magnesia were discussed. The results show that the high activity light calcined magnesia has higher defect energy and greater sintering driving force,which can promote the growth of Mg O crystals,thus improve the sintering of magnesia. But the excessively high activity decreases the densification of the specimen. Using light calcined magnesia after 900 ℃ calcining,and adopting two steps calcination at 1 700 ℃ for 3 h,the prepared sintered magnesia has 3. 41 g ·cm^-3 of bulk density,and well-developed grains,which arrange evenly and closely.
作者
郭玉香
彭强
曲殿利
姚焯
王春新
杨雨静
Guo Yu-xiang;Peng Qiang;Qu Dianli;Yao Zhuo;Wang Chunxin;Yang Yujing(School of High Temperature Materials and Magnesium Resources Engineering,University of Science and Technology Liaoning,Anshan 114051,Liaoning,China)
出处
《耐火材料》
CAS
北大核心
2018年第3期176-179,共4页
Refractories
基金
国家科技支撑计划项目(2014BAB02B01)
关键词
轻烧氧化镁
活性
烧结镁砂
烧结性能
显微结构
light calcined magnesia
activity
sintered magnesia
sintering property
microstructure
