Effects of Grain Refinement on the Low-Cycle Fatigue Behavior of IN792 Superalloys

doi:10.3390/cryst11080892

CORC > 金属研究所 > 中国科学院金属研究所

	Effects of Grain Refinement on the Low-Cycle Fatigue Behavior of IN792 Superalloys
	Du, Beining 1,2; Sheng, Liyuan 1,2; Cui, Chuanyong 3; Hu, Ziyang 4; Sun, Xiaofeng 3
刊名	CRYSTALS
	2021-08-01
卷号	11 期号:8 页码:15
关键词	Ni-based superalloy grain refinement low-cycle fatigue fracture dislocation
DOI	10.3390/cryst11080892
通讯作者	Sheng, Liyuan(lysheng@yeah.net) ; Cui, Chuanyong(chycui@imr.ac.cn)
英文摘要	The Ni-based IN792 superalloy is widely applied as a component in industrial turbines and aircraft engines due to its good high-temperature properties and excellent corrosion resistance. Since these components have to suffer from cyclic thermal and mechanical stresses during service, the high-temperature fatigue failure becomes one of the major factors affecting their service lives. Grain refinement has been considered as an effective way to improve the mechanical performance of superalloys. However, due to the complexity of alloy composition, microstructure and service condition, there is no unified theory about the influence of grain refinement on the fatigue performance and fracture mechanism of superalloys. In the present research, the IN792 superalloy with different grain sizes was manufactured. Then, fully reversed, strain-controlled, low-cycle fatigue (LCF) tests with four different total strain amplitudes were carried out on the alloy at 700 degrees C and 800 degrees C to clarify the effects of grain refinement on its LCF behavior. The results show that grain refinement improved the fatigue life significantly, which is mainly attributed to increasing the grain boundary content and refining MC carbides, eutectic structures and dendritic structures. During fatigue test under lower strain amplitude, the alloy exhibits a pronounced initial fatigue hardening followed by a continuous well-defined stability stage, which is caused by the formation of dislocation networks and coarsening of primary gamma' phases. However, during fatigue test under higher strain amplitude, the alloy exhibits continuous hardening response because the dislocations could shear primary gamma' phases, which could give rise to resistance to dislocation movement. In addition, the fracture surface observation shows that the fatigue fracture mode is mainly affected by the total strain amplitude. Under lower total strain amplitude, the fatigue microcracks mainly initiate at the porosities near the specimen surface, while under higher total strain amplitude, the fatigue microcracks tend to form at the interior of the specimen.
资助项目	National Key Research and Development Program of China[2018YFC1106702] ; Natural Science Foundation of Guangdong Province, China[2020A1515011301] ; Natural Science Foundation of Guangdong Province, China[2019A1515110067] ; Natural Science Foundation of Guangdong Province, China[2018A0303100018] ; Natural Science Foundation of Guangdong Province, China[2018A030313950] ; Shenzhen Basic Research Project[JCYJ20200109144608205] ; Shenzhen Basic Research Project[JCYJ20170815153143221] ; Shenzhen Basic Research Project[JCYJ20210322085719002] ; IER Foundation[HT-JD-CXY-201902] ; IER Foundation[HT-JD-CXY-201907]
WOS研究方向	Crystallography ; Materials Science
语种	英语
出版者	MDPI
WOS记录号	WOS:000689009400001
资助机构	National Key Research and Development Program of China ; Natural Science Foundation of Guangdong Province, China ; Shenzhen Basic Research Project ; IER Foundation
内容类型	期刊论文
源URL	[http://ir.imr.ac.cn/handle/321006/166871]
专题	金属研究所_中国科学院金属研究所
通讯作者	Sheng, Liyuan; Cui, Chuanyong
作者单位	1.Peking Univ, Shenzhen Inst, Shenzhen 518057, Peoples R China 2.PKU HKUST Shenzhen HonKong Inst, Shenzhen 518057, Peoples R China 3.Chinese Acad Sci, Inst Met Res, Shenyang 110016, Peoples R China 4.Shenzhen Yezhan Elect Co Ltd, Shenzhen 518110, Peoples R China
推荐引用方式 GB/T 7714	Du, Beining,Sheng, Liyuan,Cui, Chuanyong,et al. Effects of Grain Refinement on the Low-Cycle Fatigue Behavior of IN792 Superalloys[J]. CRYSTALS,2021,11(8):15.
APA	Du, Beining,Sheng, Liyuan,Cui, Chuanyong,Hu, Ziyang,&Sun, Xiaofeng.(2021).Effects of Grain Refinement on the Low-Cycle Fatigue Behavior of IN792 Superalloys.CRYSTALS,11(8),15.
MLA	Du, Beining,et al."Effects of Grain Refinement on the Low-Cycle Fatigue Behavior of IN792 Superalloys".CRYSTALS 11.8(2021):15.