低温碳热合成工艺一步法制备超细碳化铌的实验研究  

Experimental Research on One-Step Preparation of Ultrafine Niobium Carbide by Low-Temperature Carbothermal Synthesis Process

作　　者：杨昭 贾中帅 史培阳 白倩慧 YANG Zhao;JIA Zhong-shuai;SHI Pei-yang;BAI Qian-hui(Mining Research Institute of Baogang Group,Baotou 014000,China;School of Metallurgy,Northeastern University,Shenyang 110819,China)

机构地区：[1]包钢集团矿山研究院,内蒙古包头014000 [2]东北大学冶金学院,辽宁沈阳110819

出　　处：《稀有金属与硬质合金》2024年第5期55-61,共7页Rare Metals and Cemented Carbides

摘　　要：为解决一步碳化法生产碳化铌过程中产品质量差、反应时间长以及能耗高等问题,实验选用粒度相对较好控制的氢氧化铌(Nb(OH)_(5))为原料,炭黑为还原剂,采用一步碳化法直接制备纯度较高的纳米碳化铌。通过XRD和SEM分析了配碳比(Nb(OH)_(5)与炭黑质量比)、球磨时间、还原温度和还原时间对NbC产品的物相组成和显微结构的影响。实验结果表明,配碳比过高时,炭黑将阻碍Nb(OH)_(5)的热分解,从而导致还原不充分;随着原料球磨时间的延长、碳化温度的升高以及还原时间的延长,NbC产品的纯度均先增大后趋于稳定。从节能和纳米材料制备角度考虑,优化的工艺参数如下:配碳比1∶0.3、球磨时间1h、还原温度1300℃、还原时间3h。在优化实验条件下,所得NbC产品的纯度高达98.9%,且粒度小于200nm。In order to solve the problems of poor product quality,long reaction time and high energy con-sumption in the one-step carbonization production process of niobium carbide,Nb(OH)_(5) with relatively well controlled particle size was selected as the experimented raw material,carbon black was used as the re-ducing agent,and after ball minning and mixing,nano niobium carbide with high purity was directly pre-pared by one-step carbonization method.The effects of carbon fitting ratio(mass ratio of Nb(OH)_(5) to car-bon black),ball milling time,reduction temperature and reduction time on the phase composition and mi-crostructure of NbC product were analyzed by XRD and SEM.The experimental results show that when the carbon fitting ratio is too high,the carbon black hinders the thermal decomposition of Nb(OH)_(5),which leads to insufficient reduction.With the extension of ball milling time of the raw material,the increase of carbonization temperature and the extension of the reduction time,the purity of NbC product increases firstly and then tends to be stable.In view of energy saving and nanomaterial preparation,the optimized process parameters are as follows:carbon fitting ratio of 1∶0.3,ball milling time of 1 h,reduction tempe-rature of 1300℃,and reduction time of 3 h.Under the optimized experimental conditions,the purity of the obtained NbC product reaches 98.9%,and the particle size is less than 200 nm.

关 键 词：氢氧化铌 碳化铌 纳米材料 一步碳化法 球磨 配碳比 还原 

分 类 号：TQ135.12[化学工程—无机化工]