摘要
目前氮化钛主要采用钛粉直接氮化生产,但生产过程需多次氮化,能耗较高。以氟钛酸钠为原料经铝热还原制备的多孔钛比表面积大、活性好,本文对以多孔钛为原料直接氮化制备氮化钛的工艺进行研究。通过X射线衍射仪、扫描电镜和氧氮氢分析仪,分别对所制备氮化钛的物相、微观形貌和N含量进行分析,研究氮化工艺条件对氮化效果的影响。通过热力学分析和差热-热重分析探讨了多孔钛直接氮化的机理。结果表明,在氮化温度1200℃、保温时间300min、氮化压力0.100MPa的条件下,经一次氮化即可制备N含量为20.6%的氮化钛,制备的氮化钛纯度较高,整体氮化效果较好。多孔钛的氮化是放热反应,由于渗氮过程是由表及里逐渐进行的,而且N元素由颗粒表面向内扩散的过程较慢,氮化反应整体上是一个缓慢氮化、逐渐增氮的过程。
At present,titanium nitride is produced mainly by direct nitridation of titanium powder,but the production process requires multiple nitridation,resulting in high energy consumption,Porous titanium prepared by aluminothermic reduction with sodium fluorotitanate as raw material has large specific surface area and good activity.The process of preparing titanium nitride by direct nitridation of porous titanium as raw material is studied in this paper.The phase,microstructure and nitrogen content of the prepared titanium nitride were analyzed by XRD,SEM and ONH,and the influence of nitridation process conditions on nitridation effect was studied.The mechanism of direct nitridation of porous titanium was discussed by thermodynamic analysis and differential thermal-thermogravimetric analysis.The results show that titanium nitride with N content of 20.6%can be prepared by one-stage nitridation under the conditions of nitridation temperature of 1200 C,holding time of 300 min and nitridation pressure of o.100 MPa.The purity of the prepared titanium nitride is high and the overall nitridation effect is good.The nitridation of porous titanium is exothermic.Since the nitridation process is gradually from the surface to the inside and the N element diffuses slowly from particle surface to the inside,the nitridation reaction as a whole is a process of slowly nitriding and gradually increasing nitrogen.
作者
邱炜宸
王耀武
狄跃忠
彭建平
QIU Wei-chen;WANG Yao-wu;DI Yue-zhong;PENG Jian-ping(School of Metallurgy,Northeastern University,Shenyang 110004,China;Shenyang Foundry Research Institute Co.,Ltd.,Shenyang 110023,China)
出处
《稀有金属与硬质合金》
CAS
CSCD
北大核心
2022年第4期77-82,共6页
Rare Metals and Cemented Carbides
基金
国家自然科学基金项目(21878045,51674076)
河北省科技重大专项(20281003Z)。
关键词
氮化钛
直接氮化
多孔钛
铝热还原
氮化机理
N含量
titanium nitride
direct nitridation
porous titanium
aluminothermic reduction
nitridation mechanism
nitrogen content
