Effect of Nb addition on microstructure of Fe-Co-2V soft magnetic alloy

doi:10.13251/j.issn.0254-6051.2020.02.014

Abstract

Abstract:

Fe-49Co-2V and Fe-49Co-2V-0.3Nb alloys were hot and cold rolled into sheets respectively, then annealed at 850 ℃ for 2 h. The microstructure of the alloys was investigated by means of transmission electron microscope(TEM) and selected area electron diffraction(SAED). The results show that the adding of Nb facilitates the formation of precipitates, which is small particles composed with Nb, Co and Fe, while V is not detected. The chemical formula of the precipitate is Co₃Nb, in which some Co atoms are partly substituted by Fe atoms. The precipitates in different shapes are also detected in as-cast specimens which might be the source of precipitates in the sheet specimens. In addition, lath-like twin structures are detected closing to the precipitates in the alloy containing Nb, which might be beneficial to the improvement of ductility and grain refinement.

Key words: Fe-Co soft magnetic alloy, precipitation, SAED, annealing twin

CLC Number:

TG113

Wang Xuandong, Wang Dongling, Zhang Jinglin, Yu Yipeng, Wu Bin, Zhang Jianfu. Effect of Nb addition on microstructure of Fe-Co-2V soft magnetic alloy[J]. HTM, 2020, 45(2): 72-75.

References

[1]Clegg D W, Buckley R A. The disorder-order transformation in iron-cobalt-based alloys[J]. Metal Science Journal, 1973, 7: 48-54.
[2]White J H, Wahl C V. Workable magnetic compositions containing principally iron and cobalt[P]. US patent No. 1862559, 1932.
[3]穆丹宁, 杨长林, 魏晓伟, 等. FeCo基合金软磁材料研究进展[J]. 稀有金属材料与工程, 2013, 42(6): 1316-1320.
Mu Danning, Yang Changlin, Wei Xiaowei, et al. Research development of FeCo alloy soft magnetic materials[J]. Rare Metal Materials and Engineering, 2013, 42(6): 1316-1320.
[4]Sundar R S, Deevi S C. Soft magnetic FeCo alloys: Alloy development, processing, and properties[J]. International Materials Reviews, 2005, 50(3): 157-192.
[5]Hou C Q, Shan Y J, Wu H C, et al. Effect of a small addition of Cr on soft magnetic and mechanical properties of Fe-49Co-2V alloy[J]. Journal of Alloys and Compounds, 2013, 556: 51-55.
[6]Branson M W, Major R V, Pitt C, et al. A study of the microstructure and related magnetic/mechanical properties of some iron-cobalt-vanadium and iron-cobalt-vanadium-nickel alloys[J]. Journal of Magnetism and Magnetic Materials, 1980, 19(1): 222-224.
[7]Persiano A I C, Rawlings R D. Effect of niobium additions on the structure and magnetic properties of equiatomic iron-cobalt alloys[J]. Journal of Materials Science, 1991, 26(15): 4026-4032.
[8]Hailer B T. Effect of heat treatment on magnetic and mechanical properties of iron-cobalt-vanadium-niobium alloy[D]. Virginia, Blacksburg: Virginia Polytechnic Institute, 2001.
[9]韩劲, 倪志铭, 杨根林, 等. 高温高强度Fe-Co软磁合金研制[J]. 功能材料, 2015, 46(21): 21076-21080.
Han Jin, Ni Zhiming, Yang Genlin, et al. Study on soft magnetic Fe-Co alloys with high strength and high temperature resistant[J]. Journal of Functional Materials, 2015, 46(21): 21076-21080.
[10]Kawahara K, Uehara M. A possibility for developing high strength soft magnetic materials in FeCo-X alloys[J]. Journal of Materials Science, 1984, 19(8): 2575-2581.
[11]Fingers R T, Carr R P, Turgut Z. Effect of aging on magnetic properties of Hiperco 27, Hiperco 50 and Hiperco 50HS[J]. Journal of Applied Physics, 2002, 91(10): 7848-7850.
[12]Yu R H, Zhu J. Precipitation and high temperature magnetic properties of FeCo-based alloys[J]. Journal of Applied Physics, 2005, 97(5): 053905-053906.
[13]Ashby J A, Flower H M, Rawlings R D. Gamma phase in an Fe-Co-2%V alloy[J]. Metal Science, 1977, 11(3): 91-96.
[14]Yu R H, Basu S, Zhang Y, et al. Magnetic domains and coercivity in FeCo soft magnetic alloys[J]. Journal of Applied Physics, 1999, 85(8): 6034-6036.
[15]Stein F, Jiang D, Palm M, et al. Experimental reinvestigation of the Co-Nb phase diagram[J]. Intermetallics, 2008, 16(6): 785-792.
[16]杨钢, 孙利军, 张丽娜, 等. 形变孪晶的消失与退火孪晶的形成机制[J]. 钢铁研究学报, 2009, 21(2): 39-43.
Yang Gang, Sun Lijun, Zhang Lina, et al. Annihilation of deformation twins and formation of annealing twins[J]. Journal of Iron and Steel Research, 2009, 21(2): 39-43.