Ni_2O_3掺杂MgO-CaO材料的烧结性研究  

Sintering property of MgO-CaO material doped with Ni_2O_3

作　　者：丁雄风 赵惠忠[1] 张寒[1] 

机构地区：[1]武汉科技大学省部共建耐火材料与冶金国家重点实验室,湖北武汉430081

出　　处：《耐火材料》2015年第4期273-275,280,共4页Refractories

基　　金：国家级大学生创业训练计划项目("大别山白云石矿的开发与利用"201210488086)

摘　　要：为了在不降低Mg O-Ca O材料高温性能的前提下促进其烧结,将分析纯Mg(OH)2和Ca(OH)2按3 1的质量比配料,经球磨、轻烧后,分别掺加0、0.5%、0.75%、1%(w)的分析纯Ni2O3,再经混练、消化、困料、成型、烘干后,经1 650℃3 h烧成冷却后,检测烧后试样的显气孔率和体积密度,并进行XRD和SEM分析。结果表明:随着Ni2O3引入量从0增加到0.75%(w),Mg O-Ca O材料的烧结致密化程度逐渐增大,但超过0.75%(w)后反而减小。Ni2O3在烧结过程中分解为Ni O,进而与Mg O形成连续固溶体,增强Mg2+的扩散率,促进Mg O-Ca O体系中Mg2+和Ca2+的互扩散,有利于晶粒的生长发育和试样的烧结致密化。In order to improve the sintering properties and to maintain the hot properties of MgO-CaO mate- rials,analytical pure Mg（OH）2 and Ca（OH）2 with mass ratio of 3：1 were ball milled and light burned,and Ni2 03 was added as dopant （0,0.5 % ,0. ？5 % and 1%, respectively, in mass）, followed by mulling, slaking, ageing, molding,drying,and finally firing at l 650 ℃ for 3 h. The bulk density and apparent porosity of the specimens were determined,and the specimens were also analyzed by XRD and SEM. The results show that.the sintering densification degree of MgO-CaO material rises as the Ni203 addition increases from 0 to 0.75%, but it decreases when Ni2O3 addition exceeds 0.75%. Ni203 decomposes into NiO during heating, forming continuous solid solution with MgO. The formation of the solid solution increases the diffusion mobil- ity of Mg2＋ and the mutual diffusion rate between Mg2＋ and Ca2＋ ,which promote the grain growth and sin- tering densification of MgO-CaO materials.

关 键 词：Ni2O3 MgO-CaO材料 烧结性 MgO-NiO固溶体 

分 类 号：TQ175[化学工程—硅酸盐工业]