渗硅TiAl基合金高温循环氧化动力学分析  

Analysis on High Temperature Cyclic Oxidation Kinetics of Siliconized TiAl-Based Alloy

作　　者：彭彩霞[1] 马晓霞[1] 梁伟[1] 赵兴国[1] 候增寿[1] 

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024

出　　处：《金属热处理》2007年第8期59-62,共4页Heat Treatment of Metals

基　　金：国家自然科学基金(50171046);教育部博士点基金(20050112001);山西省自然科学基金(2006011051;20021051;20021052)

摘　　要：用最小二乘法对渗硅TiAl基合金在900、1000、1100和1200℃的循环氧化数据进行了拟合。结果表明:渗硅TiAl基合金900℃氧化在所测试的118h内氧化动力学曲线呈抛物线规律;1000℃氧化在0～50h之间呈抛物线型规律,50～118h之间呈直线型氧化规律;1100℃氧化在0～4h之间呈抛物线型规律,4～8h之间呈直线型氧化规律,8～16h呈二次型加速氧化规律,16h出现剥落现象;1200℃循环氧化在0～4h呈二次型加速氧化规律,4h后出现剥落现象。相应的氧化速率常数为:900℃时Kp≈4·924×10-5mg2cm-4h-1,1000℃时Kp≈7·778×10-5mg2cm-4h-1,1100℃时Kp≈9·392×10-2mg2cm-4h-1。并对渗硅层在温度超过1000℃后的氧化机制进行了初步探讨。The cyclic oxidation resistance of pack siliconized TiAl-based alloy was tested at 900 ℃, 1000 ℃, 1100 ℃ and 1200 ℃. The results show that three kinds of oxidation kinetics behavior, parabolic, linear and quadratic, are revealed by analyzing the experimental data with least square method. At 900 ℃ , only parabolic oxidation behavior appeares during the whole cyclic oxidation test of 118 h. At 1000 ℃, the oxidation behavior is parabolic at the initial stage up to 50 h,and becomes linear from 50 h to 118 h. At 1100 ℃ ,the oxidation behavior is parabolic at the initial stage up to 4 h,and becomes linear from 4 h to 8 h,and then becomes quadratic from 8 to 16 h,and spallation occurs at the time of 16 h. At 1200 ℃, only quadratic oxidation behavior appears during the whole cyclic oxidation test period of 4 h, and spallation occurs. The corresponding oxidation constants obtained by fitting the curves are：Kp≈4. 924 × 10^-5 mg^2cm^-4 h^-1 at 900 ℃ ,Kp≈7. 778 × 10^-5 mg^2cm^-4h^-1 at 1000 ℃ ,Kp ≈9. 392 × 10^-2 mg^2cm^-4h^-1 at 1100 ℃. The oxidation mechanism of the temepature above 1000 ℃ was discussed.

关 键 词：TIAL基合金 抗氧化 表面处理 化学热处理 氧化动力学 

分 类 号：TG156.8[金属学及工艺—热处理]