草酸盐法制备硼酸镁晶须及其生长机理  

Preparation of Mg_2B_2O_5 Whisker by Oxalate Method and Its Growth Mechanism

作　　者：尹正帅 李勇[2] 薛向欣[2] 

机构地区：[1]湖北三江航天江北机械工程有限公司,孝感432000 [2]东北大学材料与冶金学院,沈阳110819

出　　处：《材料导报》2013年第14期38-41,共4页Materials Reports

基　　金：国家自然科学基金(50774022);国家高技术研究发展计划(863计划)(2006AA06Z368)

摘　　要：以MgCl2·6H2O、H3BO3和H2C2O4·2H2O为原料,利用草酸盐法制备出长度为4.0～8.0μm,直径为0.6～1.5μm,长径比约为10,形貌良好的硼酸镁晶须。采用XRD、SEM及TG-DTA等分析手段,研究了烧结温度、烧结时间、n(B)/n(Mg)、n(H2C2O4)/n(Mg)对硼酸镁晶须的生长过程和质量的影响,探讨了其最佳制备条件。结果显示,硼酸镁晶须的最佳制备条件为:烧结温度为800℃,烧结时间为4.0h,n(B)/n(Mg)=1.2,n(H2C2O4)/n(Mg)=1.2。根据XRD和TG-DTA分析,MgC2O4前驱体对硼酸镁晶须的形成和生长有较大的促进作用,分解产物不引入其它杂质,使得制备的晶须纯度较高。晶须的生长机理为S-L-S机理。With MgCl2 · 6H2O, HaBO3 and H2C2O4 · 2H2O as raw materials, magnesium borate whiskers were synthesized by oxalate method. The lengths of the whiskers varied from 4. 0 μm to 8. 0μm, the diameters varied from 0.6 μm to 1.5 tam, and the aspect ratio was about 10. The produced samples were characterized by XRD, SEM, and TG-DTA. The effects of reaetion temperature, reaction time, n（B）/n（Mg）, and n（H2C2O4）/n（Mg） on the whisker growth process and product quality were explored. The best preparation conditions were obtained. It was found that the best prepared parameters of reaction temperature, reaction time, n （B）/n （Mg）, and n （ Hz C4 04 ） / n（Mg） were 800 ℃ ,4. 0 h,1.2 and 1.2, respectively. According to the XRD and TG-DTA analysis, MgC2O4 precur- sor greatly promotes the formation and growth of Mg2 132 O2 whiskers, its decomposition products do not introduce im- purities,making the whiskers more purity. The whisker growth process is solid-liquid-solid （S-L-S） mechanism.

关 键 词：草酸盐法 制备 硼酸镁晶须 S-L-S机理 

分 类 号：TB132[理学—物理]