Kinetic study on NaF-activated pack-aluminizing of pure titanium at 950-1100℃  

950～1100℃下纯钛NaF活化包埋渗铝的动力学研究(英文)

作　　者：H.R.KARIMI ZARCHI M.SOLTANIEH M.R.ABOUTALEBI X.GUO 

机构地区：[1]Centre of Excellence for High Strength Alloys Technology,School of Metallurgy and Materials Engineering,Iran University of Science and Technology [2]State Key Laboratory of Solidification Processing,Northwestern Polytechnical University

出　　处：《Transactions of Nonferrous Metals Society of China》2014年第6期1959-1968,共10页中国有色金属学报（英文版）

摘　　要：Pure titanium samples were aluminized at 950,1025 and 1100 ℃ for 0-6 h in a pack containing 10%Al＋5%NaF＋85%Al2O3 in mass traction.The aluminized layers formed on the samples were characterized.The kinetic studies indicated that the diffusion of Al-bearing gases through the pack is the rate-controlling step in this process.The activation energy of 161.8 kJ/mol was calculated for this step.In addition,the mass gains of the aluminized samples were predicted using the partial pressures of gases in the pack and those adjacent to the samples surface.The predicted values are in good agreement wim the experimental measurements at 950 ℃ but are higher than those measured at 1025 and 1100 ℃.在温度为950、1025、1100℃,包埋层成分为10%Al＋5%NaF＋85%Al2O3（质量分数）的条件下,在纯钛上渗铝0-6 h。对样品上的渗铝层进行了表征。动力学研究表明,含铝气体通过包埋层的扩散过程是速率控制步骤。通过计算得到这个步骤的活化能为161.8 kJ/mol。通过包埋层中及样品表面气体的分压预测样品渗铝后的增重。在950℃的增重预测值与实验值吻合得很好,而在1025℃和1100℃的增重预测值比实验值高。

关 键 词：pack aluminizing titanium aluminizing aluminizing kinetics titanium aluminides 

分 类 号：TG174.44[金属学及工艺—金属表面处理]