Effects of Rare Earth elements on microstructure evolution and mechanical properties of 718H pre-hardened mold steel

doi:10.1016/j.jmst.2019.12.035

IMR OpenIR

	Effects of Rare Earth elements on microstructure evolution and mechanical properties of 718H pre-hardened mold steel
	Liu, Hanghang 1,3; Fu, Paixian 1,3; Liu, Hongwei 1,3; Cao, Yanfei 1,3; Sun, Chen 1,2,3; Du, Ningyu 1,2,3; Li, Dianzhong 1,3
通讯作者	Fu, Paixian(pxfu@imr.ac.cn) ; Li, Dianzhong(dzli@imr.ac.cn)
	2020-08-01
发表期刊	JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
ISSN	1005-0302
卷号	50 页码:245-256
摘要	718H Pre-hardened mold steels with different Rare Earth (RE) contents were prepared to investigate the influence of RE on microstructure evolution and mechanical properties through a series of experiments and theoretical analysis. The results indicated that the toal oxygen (T.O) content decreased from 15 ppm to 6 ppm with 0.022 wt% RE addition, which is attributed to the active chemical properties of RE elements. For test steels, RE additions of 0.012 wt% and 0.022 wt% were significantly effective for refining inclusions by eliminating 11.5% large-sized inclusions with diameter exceeding 10 mu m compared with that of ORE steel. RE addition contributed to modify irregular MnS and Al2O3 inclusions into ellipsoidal RE-inclusions (RE2O3, RES, RE2O2S and REAlO3). The purification of molten steel and the modification of inclusions by RE treatment have significant effects on improvement of the fatigue crack growth tests (FCG) inhibition ability and impact energy as well as the isotropy. However, excessive addition of RE elements (0.07 wt%) seriously reduced the impact energy, ultimate tensile strength and FCG inhibition ability due to rapidly increase of the volume fraction of large-sized inclusions. In addition to the inclusions formed by RE treatment, trace solid solution RE atoms improve the stability of undercooled austenite, resulting in the transformation region of bainite and perlite of 0.07RE steel shifting to the bottom right and prolonging the incubation period compared with that of ORE steel. (C) 2020 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.
关键词	718H steel Rare Earth Inclusion evolution Phase transformation Mechanical properties
资助者	China Postdoctoral Science Foundation ; National Natural Science Foundation of China
DOI	10.1016/j.jmst.2019.12.035
收录类别	SCI
语种	英语
资助项目	China Postdoctoral Science Foundation[2019M661153] ; National Natural Science Foundation of China[51701225] ; National Natural Science Foundation of China[TC190A4DA/35]
WOS研究方向	Materials Science ; Metallurgy & Metallurgical Engineering
WOS类目	Materials Science, Multidisciplinary ; Metallurgy & Metallurgical Engineering
WOS记录号	WOS:000537588800024
出版者	JOURNAL MATER SCI TECHNOL
引用统计	被引频次：63[WOS] [WOS记录] [WOS相关记录]
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/139174
专题	中国科学院金属研究所
通讯作者	Fu, Paixian; Li, Dianzhong
作者单位	1.Shenyang Natl Lab Mat Sci, Shenyang 110016, Peoples R China 2.Univ Sci & Technol China, Sch Mat Sci & Engn, Shenyang 110016, Peoples R China 3.Chinese Acad Sci, Inst Met Res, Shenyang 110016, Peoples R China
推荐引用方式 GB/T 7714	Liu, Hanghang,Fu, Paixian,Liu, Hongwei,et al. Effects of Rare Earth elements on microstructure evolution and mechanical properties of 718H pre-hardened mold steel[J]. JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY,2020,50:245-256.
APA	Liu, Hanghang.,Fu, Paixian.,Liu, Hongwei.,Cao, Yanfei.,Sun, Chen.,...&Li, Dianzhong.(2020).Effects of Rare Earth elements on microstructure evolution and mechanical properties of 718H pre-hardened mold steel.JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY,50,245-256.
MLA	Liu, Hanghang,et al."Effects of Rare Earth elements on microstructure evolution and mechanical properties of 718H pre-hardened mold steel".JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY 50(2020):245-256.