Thermodynamic and Kinetic Study on the Nitrogen-Removing Process of High Cr Content Nickel Based Alloy

IMR OpenIR

	Thermodynamic and Kinetic Study on the Nitrogen-Removing Process of High Cr Content Nickel Based Alloy
	Wang Min; Zhang Long; Yang Yaqian; Gao Ming; Ding Leilei; Ma Yingche; Liu Kui
通讯作者	Ma Yingche(ycma@imr.ac.cn)
	2020-11-01
发表期刊	RARE METAL MATERIALS AND ENGINEERING
ISSN	1002-185X
卷号	49 期号:11 页码:3803-3808
摘要	Nitrogen is one of the undesirable impurity elements of superalloys and it can induce the precipitation of nitrides and the formation of microporosity to worsen the mechanical properties of material. With the increase of high demands in superalloy component quality, nowadays the nitrogen content in superalloy has been recommended to be no higher than 10 mu g/g. Chromium is an important beneficial alloying element widely employed in superalloys (with an addition up to 20 wt%) for it can enhance the anti-corrosion performance of alloys at elevated temperature. However, chromium has a high affinity to nitrogen so that it could be very hard to achieve a low nitrogen content in high-Cr alloys. Therefore, it is necessary to study the features of the nitrogen-removing process of high-Cr alloys. In this work, the nitrogen-removing process during the vacuum induction melting of a high-Cr nickel based alloy was investigated by thermodynamic calculation and kinetic experiments. Results show that high-Cr nickel based alloy has a high thermodynamic equilibrium solubility of nitrogen, and it is mainly dominated by the vacuum pressure. In order to achieve the goal of [N]<= 10 mu g.g(-1), the melting vacuum pressure should be no higher than 0.1 Pa. To study the kinetic characteristics of nitrogen-removing process, the melted metal was held at 1500, 1550 and 1600 degrees C, and sampled at 0, 30, 60, 120, 180 and 240 min at 0.1 Pa after the complete melting of alloy. Results indicate that nitrogen content dramatically decreases at the beginning of melt holding, but in the medium and later stage it takes a much longer period of time to get close to the equilibrium solubility of nitrogen. Kinetic data analysis shows that the nitrogen-removing process of high-Cr nickel-based alloy can be classified as the second-order reaction, which reflects that the process is controlled by the chemical reaction on melt surface. The apparent rate constants of nitrogen-removing process at 1500, 1550 and 1600 degrees C are calculated to be 0.0184, 0.0233 and 0.0397 m-s(-1), respectively, and the average apparent activation energy is determined to be 211.4 kJ.mol(-1).
关键词	nickel based alloy vacuum induction melting nitrogen-removing
收录类别	SCI
语种	英语
WOS研究方向	Materials Science ; Metallurgy & Metallurgical Engineering
WOS类目	Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
WOS记录号	WOS:000596957900020
出版者	NORTHWEST INST NONFERROUS METAL RESEARCH
引用统计
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/158688
专题	中国科学院金属研究所
通讯作者	Ma Yingche
作者单位	Chinese Acad Sci, Inst Met Res, CAS Key Lab Nucl Mat & Safety Assessment, Shenyang 110016, Peoples R China
推荐引用方式 GB/T 7714	Wang Min,Zhang Long,Yang Yaqian,et al. Thermodynamic and Kinetic Study on the Nitrogen-Removing Process of High Cr Content Nickel Based Alloy[J]. RARE METAL MATERIALS AND ENGINEERING,2020,49(11):3803-3808.
APA	Wang Min.,Zhang Long.,Yang Yaqian.,Gao Ming.,Ding Leilei.,...&Liu Kui.(2020).Thermodynamic and Kinetic Study on the Nitrogen-Removing Process of High Cr Content Nickel Based Alloy.RARE METAL MATERIALS AND ENGINEERING,49(11),3803-3808.
MLA	Wang Min,et al."Thermodynamic and Kinetic Study on the Nitrogen-Removing Process of High Cr Content Nickel Based Alloy".RARE METAL MATERIALS AND ENGINEERING 49.11(2020):3803-3808.