PDF《合金元素钨对新型 Co-Al-W 合金热腐蚀行为的影响》

第21 卷第

1 期 中国有色金属学报

2011 年1月Vol.

21 No.1 The Chinese Journal of Nonferrous Metals Jan.

2011 文章编号:1004-0609(2011)01-0110-08 合金元素钨对新型 Co-Al-W 合金热腐蚀行为的影响 徐仰涛 1,

2 , 夏天东 1,

2 , 闫健强 1,

2 (1. 兰州理工大学 甘肃省有色金属新材料省部共建国家重点实验室, 兰州 730050;

2. 兰州理工大学 有色金属合金及加工教育部重点实验室, 兰州 730050) 摘要: 研究 Co-Al-W 和商用 MAN900 合金在

800 ℃ 75%Na2SO4+25%NaCl 混合熔盐中的腐蚀动力学及热腐蚀 行为. 结果表明: 7.5 W、 9.8 W 和10.7 W 合金经热腐蚀后质量增加量比 MAN900 合金的质量增加量少, Co-Al-W 合金的耐热腐蚀能力比 MAN900 合金的耐热腐蚀能力强. Co-Al-W 合金在熔盐中腐蚀膜结构分成

3 层, 即呈蓬松 状由富钴氧化物 Co3O4 组成的腐蚀膜最外层,由Co、Al、W 复杂氧化物组成的中间过渡层和主要由 Al 及Co 氧 化物组成较致密的腐蚀膜内层.随着腐蚀时间的增加,合金腐蚀膜最外层由于脱落逐渐变薄;

中间过渡层厚度逐 渐增加,该层中各元素分布趋于均匀、稳定;

腐蚀膜内层致密性增加使该层增厚不明显. 关键词: Co-Al-W 合金;

合金元素钨;

热腐蚀 中图分类号: TG172.6;

TG146.1 文献标志码:A Effect of alloying element tungsten on hot corrosion behavior of novel Co-Al-W superalloys XU Yang-tao1,

2 , XIA Tian-dong1,

2 , YAN Jian-qiang1,

2 (1. State Key Laboratory of Gansu Advanced Non-ferrous Metal Materials, Lanzhou University of Technology, Lanzhou 730050, China;

2. Key Laboratory of Non-ferrous Metal Alloys, Ministry of Education, Lanzhou University of Technology, Lanzhou 730050, China) Abstract: The hot corrosion kinetics and hot corrosion behavior of Co-Al-W and MAN900 superalloys at

800 ℃ in 75%Na2SO4+25%NaCl molten salt were studied. The results show that the mass gains of 7.5 W, 9.8 W and 10.7 W alloys are less than those of MAN900 superalloy. The hot corrosion resistance of Co-Al-W superalloys is superior to that of MAN900 superalloys. The hot corrosion oxide scale of Co-Al-W superalloys is made up of three layers, that are, the external corrosion layer consisting of Co oxide (Co3O4), the intermediate mixed oxides layer composed of complex oxide and nonuniform-barren oxide layer of Co, Al, W and an internal attacked layer with different compounds of Co, Al and O. With the increase of corrosion time, the intermediate mixed oxide layer becomes thicker, the external layer becomes thinner and internal layer almost has no change, but compactness of internal layer increases gradually. Key words: Co-Al-W superalloys;

alloying element tungsten;

hot corrosion 高温腐蚀作为多学科的交叉点,其研究必然会促 进相关学科的发展[1] .为此,许多研究者对新研制的 合金在其力学性能研究取得一定进展的前提下,对其 热腐蚀性能进行大量研究[2?6] , 提出高温腐蚀的一般机 理[7?8] . 但由于影响合金热腐蚀的因素非常复杂,如 合金的组成、合金的制备工艺、沉积物的量、腐蚀温 度及腐蚀方式等[9] ,不同合金在不同腐蚀条件下其耐 腐蚀性能会有很大差异,因此,模拟合金使用环境并 基金项目:2009 年中国科学院西部之光计划资助项目(0901ZBB066);

甘肃省中青年科技基金计划项目(099RJYA018);

兰州理工大学优秀青年教师 培养计划项目(1001ZCX009);

兰州理工大学博士科研启动基金资助项目(01-0282) 收稿日期:2009-12-31;