铝热法制备钒铝合金热力学及动力学研究  

Study on Thermodynamic and Kinetics for Preparation of Vanadium-aluminum Alloy Based on Thermite Reaction

作　　者：段生朝[1,2] 王竹青 郭汉杰 郭靖[1,2] 石骁 刘帅[1,2] 于梦曦 

机构地区：[1]北京科技大学冶金与生态工程学院,北京100083 [2]高端金属材料特种熔炼与制备北京市重点实验室,北京100083 [3]江苏镔鑫钢铁集团有限公司,江苏连云港222002

出　　处：《钢铁钒钛》2017年第6期47-54,共8页Iron Steel Vanadium Titanium

基　　金：国家自然科学基金资助(U1560203;51274031)

摘　　要：基于原子-分子理论建立了计算Al-V二元合金系结构单元质量作用浓度的热力学模型。利用文献报道的2 000、2 073、2 173、2 273 K下Al-V二元系的活度计算了生成Al8V5、Al4V反应的平衡常数,并进一步得到其摩尔标准吉布斯自由能的表达式。同时采用TG-DSC热重同步热试验分析的方法,研究了不同升温速率下,铝热法合成钒铝合金反应机理及化学反应动力学。结果发现温度在660~690℃时,差示扫描量热曲线各出现一个吸热、放热峰,说明反应机理已发生改变。然后分别运用Kissinger法、Kissinger-Crane法求解铝热反应动力学参数,建立动力学方程,通过动力学计算得到表观活化能E=448.96 k J/mol,频率因子A=1.98×10^(29)m/s,反应级数n=0.83。A thermodynamic model for calculating the mass action concentration of structural units in A1-V binary melts system was established based on the atom-molecule theory. The standard equilibrium constants for generating AlsV5 and AI4V were calculated using the activities of A1-V binary system respectively at 2 000,2 073,2 173 and 2 273 K reported on the literatures and the expressions of standard mole Gibbs free energy for the reactions were further obtained. Meanwhile, the mechanism and chemical kinetics for prepara- tion of vanadium-aluminum alloy based on thermite reaction at different heating rates were investigated by TG-DSC. There was respectively an exothermic and endothermic peak on the differential scanning calorime- try curve （DSC curve） at 660 -690 ℃ indicating the variation of reaction mechanism. The kinetics parame- ters of the thermite reactions were separately calculated by Kissinger and Kissinger-Crane equations and the kinetics equation was established. The apparent activation energy （E） was calculated to be 448.96 kJ mol-1, the frequency factor A = 1.98 × 1029 m - s-m and the reaction order n = 0.83.

关 键 词：钒铝合金 铝热法 原子-分子理论 热力学 差示扫描量热 动力学 

分 类 号：TF841.3[冶金工程—有色金属冶金] TG146[一般工业技术—材料科学与工程]