催化剂对Nb-Ti-Si-Cr基超高温合金表面Si-Zr-Y共渗层组织的影响
收稿日期: 2012-07-09
修回日期: 2012-09-13
网络出版日期: 2012-11-11
基金资助
国家自然科学基金项目50871087和高等学校学科创新引智计划项目B080401资助
EFFECTS OF ACTIVATORS ON FORMATION OF Si-Zr-Y CO-DEPOSITION COATINGS ON Nb-Ti-Si-Cr BASE ULTRAHIGH TEMPERATURE ALLOY
Received date: 2012-07-09
Revised date: 2012-09-13
Online published: 2012-11-11
Supported by
Supported by National Natural Science Foundation of China (No.50871087) and the Programme of Introducing Talents of Discipline to Universities (No.B080401)
使用不同种类催化剂(NaF, NH4F, NH4Cl, NaBr和NaCl)经1250 ℃保温8 h扩散共渗, 在新型Nb-Ti-Si-Cr基超高温合金表面制备了Si-Zr-Y共渗层, 分析了各共渗层的结构及相组成, 并对其组织形成过程进行了讨论. 结果表明: 不同种类催化剂制备的共渗层由外至内均由(Nb, X)Si2(X表示元素Ti, Cr和Hf)外层, (Ti, Nb)5Si4过渡层及富Al, Cr和Y的 (Nb, X)5Si3内层组成. 在5种催化剂中, 采用NaF和NH4F时制备的共渗层较厚、组织致密, 且采用NaF时所制备的共渗层中Zr和Y的含量较高; 采用NH4Cl, NaBr和NaCl时制备的共渗层较薄且表面分布有大量的孔洞以及ZrO2和HfO2氧化物. 渗包内Si的卤化物平衡气相分压较高时制备的共渗层较厚且组织致密; 而Zr和Y的卤化物平衡气相分压对其在共渗层中的含量没有显著影响.
关键词： Nb-Ti-Si-Cr基超高温合金; Si-Zr-Y共渗层; 组织形成; 平衡气相分压
李轩 郭喜平 . 催化剂对Nb-Ti-Si-Cr基超高温合金表面Si-Zr-Y共渗层组织的影响[J]. 金属学报, 2012 , 48(11) : 1394 -1402 . DOI: 10.3724/SP.J.1037.2012.00404
Si-Zr-Y co-deposition coatings on an Nb-Ti-Si-Cr base ultrahigh temperature alloy were prepared by pack cementation processes at 1250 ℃ for 8 h with different halide activators in the packs. The structure, constituent phases and formation process of the coatings were investigated. The results show that all the coatings are mainly composed of an (Nb, X)Si2 (X represents Ti, Cr and Hf elements) outer layer, a (Ti, Nb)5Si4 transitional layer, and an Al, Cr and Y-rich (Nb, X)5Si3 inner layer located between the coating and the substrate. In the five kinds of (NaF, NH4F, NH4Cl, NaBr and NaCl) activators investigated, the coatings prepared respectively with NaF and NH4F activators are thicker and denser, and furthermore, the contents of both Zr and Y elements are larger in the coating prepared with NaF as the activator. However, the coatings prepared respectively with NH4Cl, NaBr and NaCl as the activators are thiner, and lots of holes and ZrO2 and HfO2 particles are observed in the surface layer of the coatings. The higher equilibrium partial pressures of gaseous halide silicides in the packs resulted in thicker and denser co-deposition coatings, while the equilibrium partial pressures of gaseous halide Zr and Y in the packs have less effect on their contents in the coatings.
[1] Bewlay B P, Jackson M R, Zhao J C, Subramaniam P R. Metall Mater Trans, 2003; 34A: 2043
[2] Guo X P, Gao LM, Guan P, Kusabiraki K, Fu H Z. Mater Sci Forum, 2007; 539–543: 3690
[3] Li M, Song L X, Le J, Zhang X W, Pei B G, Hu X F. Key Eng Mater, 2005; 280–283: 907
[4] Tian X D, Guo X P. Acta Metall Sin, 2008; 44: 585
(田晓东, 郭喜平. 金属学报, 2008; 44: 585)
[5] Qiao Y Q, Guo X P. Appl Surf Sci, 2010; 256: 7462
[6] Vilasi M, Steinmetz J, Allemand B G. J Adv Mater, 2000; 32: 53
[7] Vilasi M, Francois M, Podor R, Steinmetz J. J Alloys Compd, 1998; 264: 244
[8] Chen C, Zhou C G, Gong S K, Li S S, Zhang Y, Xu H B. Intermetallics, 2007; 15: 805
[9] Tian X D, Guo X P. Surf Coat Technol, 2009; 203: 1161
[10] Zhang P, Guo X P. Surf Coat Technol, 2011; 206: 446
[11] Christensen R J, Tolpygo V K, Clarke D R. Acta Mater, 1997; 45: 1761
[12] Hong S J, Hwang G H, Han W K, Lee K S, Kang S G. Intermetallics, 2010; 18: 864
[13] Pint B A. Oxid Met, 1996; 45: 1
[14] Reddy K P R, Smialek J L, Cooper A R. Oxid Met, 1982; 17: 429
[15] Zhai J K, Ma X, Bai X D, Hou W H. Acta Aeronaut Astronaut Sin, 1994; 15: 499
(翟金坤, 马祥, 白新德, 侯卫红. 航空学报, 1994; 15: 499)
[16] Wang Y, Gao J P, Li Y P, Hu X F. J Inorg Mater, 2000: 15: 143
(王禹, 郜嘉平, 李云鹏, 胡行方. 无机材料学报, 2000; 15: 143)
[17] Chaliampalias D, Stergioudis G, Skolianos S, Vourlias G. Mater Lett, 2008; 62: 4091
[18] Xiang Z D, Datta P K. Acta Mater, 2006; 54: 4453
[19] Sanjib M, Indrakumar S, Indradev S, Parag B. J Electrochem Soc, 2008; 155D: 743
[20] Brian V C, Robert A R. Metall Mater Trans, 1995; 26A: 777
[21] Tian X D, Guo X P. Surf Coat Technol, 2009; 204: 313
[22] Zhang P, Guo X P. Acta Metall Sin, 2010; 46: 821
(张平, 郭喜平. 金属学报, 2010; 46: 821)
[23] Qi T, Guo X P. J Inorg Mater, 2009: 24: 1220
(齐 涛, 郭喜平. 无机材料学报, 2009; 24: 1220)
[24] Wang R C, Jin Z P, Liu C L. J Cent South Univ Technol, 2002; 33: 385
(王日初, 金展鹏, 柳春雷. 中南工业大学学报, 2002; 33: 385)
[25] Zhao J C, Jackson M R, Peluso L A. Mater Sci Eng, 2004; 372: 21
[26] Shao G. Intermetallics, 2004; 12: 655
[27] Yu F H, Yang G H, Han R D, Weng H M. Acta Metall Sin, 1992; 28: 145
(俞方华, 杨国华, 韩荣典, 翁惠民. 金属学报, 1992; 28: 145)
[28] Schlesinger M E, Okamoto H, Gokhale A B. J Phase Equilib, 1993; 14: 502
[29] Pan J S, Tong J M, Tian M B. Fundamentals of Materials Science. Beijing: Tsinghua University Press, 1998: 466
(潘金生, 仝建民, 田民波. 材料科学基础. 北京: 清华大学出版社, 1998: 466)
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