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第4期 邓庚凤等：Sm2fe17合金的热稳定性 .393. [3]Kobayashia K.Ohmuraa M.Sagawab M.The origin of the en- 3结论 hancement of magnetic properties in Sm2FenN.(3).J (1)Sm2Fe17合金粉末越细，其抗氧化性越差. MagnMagn Mater.2002.247:42 [4]Christodoulou C N.Komada N.Anisotropic atomic diffusion (2)当温度为1073K时，每个Sm2Fe17合金分 mechanism of N.C and H into Sm2Fe7.J Alloys Compd.1995. 子已吸收了20个氧原子，大部分Sm2Fe17合金已被 222,27 氧化 [5]Wei Y N,Sun K.Fen Y B.Structural and intrinsic magnetic (3)随着升温速度的加快，Sm2Fe17合金的氧化 properties of Sm2Fe17N,(y=2~8).J Alloys Compd.1993. 194.9 温度升高，放出的热量逐渐减小， [6]董建敏，李华，孙美坤，等.间隙原子氮对化合物REzF©1r磁性 (4)Kinssinger法计算的Sm2fe17合金在低温氧 的影响.中国稀土学报，2003,21(4)：406 化时的表观活化能Ek1=162 kJ-mol1,在高温氧化 [7]张深根，李东培，应启明，等.间隙型氦化物稀土永磁材料研究 时的E2=189.8 kJ.mol1.低温反应动力学方程 进展.金属功能材料，1999,6(5)：193 为f(a)=(1一a),而高温反应动力学方程为 [8]Yue L H,Jin D L.Lu D Y,et al.The Non isothermal kinetic f(a)=2(1-a)1.67 analysis of thermal decomposition of Mg(OH)z-物理化学学报， 2005,21(7):752 [9]邓庚风，孙光飞，陈菊芳，等.CaSm203下e体系生成SmFe17 参考文献 的研究.中国稀土学报，2005,23(3)：291 [1]Coey J M D.Sun H.Improved magnetic properties by treatment [10]邓庚风，孙光飞，陈菊芳，等.还原扩散法制备SmFe1N,磁 of Iron-based rare earth intermetallic compounds in ammonia.J 粉的研究.稀土，2005,26(6)：49 Magn Magn Mater.1990,87:251 [11]邓庚风，孙光飞，陈菊芳，等.还原扩散法制备Sm2Fc17化合物 [2]Liu T Y.Chang W C.Chen C J.et al.Nitrogenation effect of re- 的工艺研究.稀有金属，2006,30(1)：1 duction diffusion Sm2Fen7 powders.IEEE Trans Magn.1992.28 [12]刘振海，山立子，分析化学手册第八分册一热分析.2 (5):2593 版.北京：化学工业出版社，2000：47 Thermal stability of Sm2Fe17 alloy DENG Gengfeng),SUN Guangfei),CHEN Jufang,FANG Keming) 1)Metallurgical and Ecological Engineering School,University of Science and Technology Beijing.Beijing 100083.China 2)Material and Chemical Engineering School.Jiangxi University of Science and Technology,Ganzhou 341000.China 3)Materials Science and Engineering School.University of Science and Technology Beijing.Beijing 100083.China ABSTRACT The effects of particle size and heating rate on the thermal stability of Sm2Fe17 alloy were investi- gated by TG/DTA technique.Chemical reactions during the oxidation of Sm2Fei7 alloy were confirmed with XRD and TG/DTA results.The apparent activation energy of the oxidation of Sm2Fe17 alloy was calculated by the Kinssinger equation and the reaction mechanism was deduced.The results show that the thermal stability of Sm2Fei7 alloy decreases with the decrease in particle size;and the sooner the heating rate is,the higher tempera- ture needs for Sm2Fei7 alloy being oxidized and the less thermal it gives out.Further studies indicate that the ap- parent activation energies of low temperature oxidation and high temperature oxidation of Sm2Fe17 alloy are 162 kJ'mol and 189.8 kJ-mol"厂，respectively. KEY WORDS rare earth permanence magnet:thermal stability:activation energy:thermal analysis:X ray diffraction analysis3 结论 （1） Sm2Fe17合金粉末越细其抗氧化性越差． （2） 当温度为1073K 时每个 Sm2Fe17合金分 子已吸收了20个氧原子大部分 Sm2Fe17合金已被 氧化． （3） 随着升温速度的加快Sm2Fe17合金的氧化 温度升高放出的热量逐渐减小． （4） Kinssinger 法计算的 Sm2Fe17合金在低温氧 化时的表观活化能 Ek1＝162kJ·mol －1在高温氧化 时的 Ek2＝189∙8kJ·mol －1．低温反应动力学方程 为 f （α） ＝ （1－α）而高温反应动力学方程为 f （α）＝2（1－α） 1∙67． 参 考 文 献 ［1］ Coey J M DSun H．Improved magnetic properties by treatment of Iron-based rare earth intermetallic compounds in ammonia．J Magn Magn Mater199087：251 ［2］ Liu T YChang W CChen C Jet al．Nitrogenation effect of reduction-diffusion Sm2Fe17powders．IEEE Trans Magn199228 （5）：2593 ［3］ Kobayashia KOhmuraa MSagawab M．The origin of the enhancement of magnetic properties in Sm2Fe17N x （0＜ x ＜3）．J Magn Magn Mater2002247：42 ［4］ Christodoulou C NKomada N． Anisotropic atomic diffusion mechanism of NC and H into Sm2Fe17．J Alloys Compd1995 222：27 ［5］ Wei Y NSun KFen Y B．Structural and intrinsic magnetic properties of Sm2Fe17Ny （ y ＝2～8）．J Alloys Compd1993 194：9 ［6］ 董建敏李华孙美坤等．间隙原子氮对化合物 RE2Fe17磁性 的影响．中国稀土学报200321（4）：406 ［7］ 张深根李东培应启明等．间隙型氮化物稀土永磁材料研究 进展．金属功能材料19996（5）：193 ［8］ Yue L HJin D LLu D Yet al．The Non-isothermal kinetic analysis of thermal decomposition of Mg（OH）2．物理化学学报 200521（7）：752 ［9］ 邓庚凤孙光飞陈菊芳等．Ca－Sm2O3－Fe 体系生成 Sm2Fe17 的研究．中国稀土学报200523（3）：291 ［10］ 邓庚凤孙光飞陈菊芳等．还原扩散法制备 Sm2Fe17N x 磁 粉的研究．稀土200526（6）：49 ［11］ 邓庚凤孙光飞陈菊芳等．还原扩散法制备 Sm2Fe17化合物 的工艺研究．稀有金属200630（1）：1 ［12］ 刘振海 山立子．分析化学手册第八分册－－－热分析．2 版．北京：化学工业出版社2000：47 Thermal stability of Sm2Fe17alloy DENG Gengfeng 12）SUN Guangfei 3）CHEN Juf ang 3）FA NG Keming 1） 1） Metallurgical and Ecological Engineering SchoolUniversity of Science and Technology BeijingBeijing100083China 2） Material and Chemical Engineering SchoolJiangxi University of Science and TechnologyGanzhou341000China 3） Materials Science and Engineering SchoolUniversity of Science and Technology BeijingBeijing100083China ABSTRACT The effects of particle size and heating rate on the thermal stability of Sm2Fe17alloy were investigated by TG／DTA technique．Chemical reactions during the oxidation of Sm2Fe17 alloy were confirmed with XRD and TG／DTA results．The apparent activation energy of the oxidation of Sm2Fe17 alloy was calculated by the Kinssinger equation and the reaction mechanism was deduced．The results show that the thermal stability of Sm2Fe17 alloy decreases with the decrease in particle size；and the sooner the heating rate isthe higher temperature needs for Sm2Fe17alloy being oxidized and the less thermal it gives out．Further studies indicate that the apparent activation energies of low-temperature oxidation and high-temperature oxidation of Sm2Fe17 alloy are 162kJ·mol －1 and189∙8kJ·mol －1respectively． KEY WORDS rare earth permanence magnet；thermal stability；activation energy；thermal analysis；X－ray diffraction analysis 第4期 邓庚凤等： Sm2Fe17合金的热稳定性 ·393·