Development of novel ferritic steels strengthened by the Co16X6Si7-G phase: A theoretical and experimental study

Wang，Cuiping1,2; Huang，Xiang1,2; Yang，Mujin3; Han，Jiajia1,2; Yao，Zhifu4,5; Yang，Tao6; Zhao，Yilu4,5; Liu，Weihong4,5; Huang，Liangfeng1,2; Huang，Chao4,5; Pan，Shaobin1,2; Li，Zhou4,5; Wang，Chenglei4,5; Chen，Youheng1,2; Yang，Chen1,2; Liu，Xingjun1,2,4,5

2022-10-01

10.1016/j.matdes.2022.111021

Materials and Design   Impact Factor & Quartile

0264-1275

1873-4197

This work aims to develop a novel CoXSi-G (X = Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, Mn, Tc, Re) phase strengthened ferritic steel with the help of first-principles calculations. Ddensity function theory calculation results demonstrated that the CoXSi-G phase possesses the advantage of good thermodynamic stability and low misfit with the ferritic matrix. On the basis of calculation, we successfully prepared three model alloys, i.e., the Fe20Cr5Co2Si1Ti, Fe20Cr5Co2Si0.75Nb and Fe20Cr5Co2Si1.5Ta (wt.%), who make a good trade-off between strength, ductility and good oxidation/corrosion resistance. Our observation verified that the CoXSi-G phase can precipitate within 1 h with proper heat treatment, showing a cube-on-cube orientation relationship with its parent matrix. The introduction of G phase precipitates amazingly increases the micro-hardness of model alloys by ∼ 160 HV after aging at 873 K. And the precipitates within the ferrite phase have not been observed to grow coarser even after 96 hrs aging treatment. Furthermore, excellent mechanical properties of ∼ 1.2 GPa tensile strength and ∼ 10 % total elongation have been achieved after 6 hrs aging time at 873 K. These findings indicate the CoXSi-G phase would be a promising candidate as a strengthening medium and provide valuable insight into the screen of precipitates for the development of high-strength and ductile steels.

Elastic properties First-principles calculations G phase Precipitation strengthening Structural stability

SCI ; EI

English

Corresponding

National Nature Science Foundation of China["51971082","11975191","52001098"] ; National Post -doctoral Program for Innovative Talents[BX20200103] ; China postdoctoral science foundation[2020M681092]

Materials Science

Materials Science, Multidisciplinary

WOS:000844333000006

ELSEVIER SCI LTD

20223312578854

Economic and social effects ; Ferrite ; High strength steel ; Microhardness ; Stability ; Strengthening (metal) ; Tensile strength

Metallurgy:531.1 ; Metallography:531.2 ; Steel:545.3 ; Mathematics:921 ; Materials Science:951 ; Social Sciences:971

MATERIALS SCIENCE

2-s2.0-85135853937

Scopus

1.College of Materials and Fujian Key Laboratory of Materials Genome,Xiamen University,Xiamen,361005,China
2.Xiamen Key Laboratory of High Performance Metals and Materials,Xiamen University,Xiamen,361005,China
3.Department of Mechanical and Energy Engineering,Southern University of Science and Technology,Shenzhen,518055,China
4.School of Materials Science and Engineering,and Institute of Materials Genome & Big Data,Harbin Institute of Technology,Shenzhen,518055,China
5.State Key Laboratory of Advanced Welding and Joining,Harbin Institute of Technology,Shenzhen,150001,China
6.Department of Materials Science and Engineering,City University of Hong Kong,Hong Kong

Wang，Cuiping,Huang，Xiang,Yang，Mujin,et al. Development of novel ferritic steels strengthened by the Co16X6Si7-G phase: A theoretical and experimental study[J]. Materials and Design,2022,222.

Wang，Cuiping.,Huang，Xiang.,Yang，Mujin.,Han，Jiajia.,Yao，Zhifu.,...&Liu，Xingjun.(2022).Development of novel ferritic steels strengthened by the Co16X6Si7-G phase: A theoretical and experimental study.Materials and Design,222.

Wang，Cuiping,et al."Development of novel ferritic steels strengthened by the Co16X6Si7-G phase: A theoretical and experimental study".Materials and Design 222(2022).