STUDY ON THE PRECIPITATION AND DISSOLUTION OF sigma PHASE IN A HOT CORROSION RESISTANCE CAST NICKLE BASE SUPERALLOY
文献类型:期刊论文
作者 | Hou Jieshan; Guo Jianting; Yuan Chao; Zhou Lanzhang |
刊名 | ACTA METALLURGICA SINICA
![]() |
出版日期 | 2016-02-11 |
卷号 | 52期号:2页码:168-176 |
关键词 | nickel base superalloy long-term exposure precipitation dissolution sigma phase |
ISSN号 | 0412-1961 |
通讯作者 | Zhou Lanzhang(lzz@imr.ac.cn) |
英文摘要 | The experimental alloy is designed and employed in high-performance industrial gas turbines as low-pressure turbine blades, working in temperature range of 750 similar to 900 degrees C. The alloy contains high levels of refractory elements in order to increase the high-temperature mechanical properties. However, this can make the alloy prone to the formation of sigma phase during service, which could deteriorate the properties further if the fraction of sigma phase exceeds the safety allowances. In this study, the formation of sigma phase during long-term thermal exposure, dissolution of the sigma phase during rejuvenation process and their influence on stress-rupture properties of a hot-corrosion resistant nickel base superalloy have been investigated. During long-term thermal exposure at 800 similar to 900 degrees C for up to 1 x 10(4) h, the sigma phase formation is mainly in dendrite cores with a few at interdendritic regions. As the aging temperature increases, the precipitation rate of sigma phase increases and the incubation time for nucleation of sigma phase decreases. From the kinetic analysis, the sigma phase form firstly in the vicinity or on the M23C6 in dendrite cores with the strong segregation of W, Cr and Co. The calculated activation energies of a formation show that the early stage is related to Co and Cr diffusions and the steady stage is related to Mo diffusion. During solid solution process at 1000 similar to 1170 degrees C the sigma phase precipitated during long-term thermal exposure dissolves to gamma matrix. As the solid solution temperature is higher, the dissolution of a phase becomes faster. Moreover, the sigma phase does not embrittle the alloy. The reheat treatment of the alloy leads to the dissolution of precipitated sigma phase and further prolongs the stress-rupture life efficiently. |
资助项目 | National Natural Science Foundation of China[30170302] ; National Natural Science Foundation of China[51571191] |
WOS研究方向 | Metallurgy & Metallurgical Engineering |
语种 | 英语 |
WOS记录号 | WOS:000371849600006 |
出版者 | SCIENCE PRESS |
资助机构 | National Natural Science Foundation of China |
源URL | [http://ir.imr.ac.cn/handle/321006/121743] ![]() |
专题 | 金属研究所_中国科学院金属研究所 |
通讯作者 | Zhou Lanzhang |
作者单位 | Chinese Acad Sci, Inst Met Res, Shenyang 110016, Peoples R China |
推荐引用方式 GB/T 7714 | Hou Jieshan,Guo Jianting,Yuan Chao,et al. STUDY ON THE PRECIPITATION AND DISSOLUTION OF sigma PHASE IN A HOT CORROSION RESISTANCE CAST NICKLE BASE SUPERALLOY[J]. ACTA METALLURGICA SINICA,2016,52(2):168-176. |
APA | Hou Jieshan,Guo Jianting,Yuan Chao,&Zhou Lanzhang.(2016).STUDY ON THE PRECIPITATION AND DISSOLUTION OF sigma PHASE IN A HOT CORROSION RESISTANCE CAST NICKLE BASE SUPERALLOY.ACTA METALLURGICA SINICA,52(2),168-176. |
MLA | Hou Jieshan,et al."STUDY ON THE PRECIPITATION AND DISSOLUTION OF sigma PHASE IN A HOT CORROSION RESISTANCE CAST NICKLE BASE SUPERALLOY".ACTA METALLURGICA SINICA 52.2(2016):168-176. |
入库方式: OAI收割
来源:金属研究所
浏览0
下载0
收藏0
其他版本
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。