The Magneto-mechanical Evolution and Degradation of NdFeB Alloys in Launch Environment

doi:10.12382/bgxb.2025.0205

Abstract

Abstract:

To fundamentally resolve the fluid leakage in the traditional hydraulic artillery recoil mechanism,the magneto-mechanical stability of neodymium iron boron (NdFeB) high-strength magnetic materials under artillery impact environment is studied to achieve the innovative applications of eddy current principle in recoil systems.In view of the situation of unclear dynamic magneto-mechanical degradation law of NdFeB,a magneto-mechanical constitutive model suitable for brittle materials is established based on thermodynamic theory and damage evolution.The dynamic mechanics and impact demagnetization experiments are carried out,and the key parameters of the magneto-mechanical constitutive model are identified on the basis of the experimental data.A dynamic calculation model of artillery is built,and the proposed constitutive model is embedded in the dynamic explicit calculation via the subroutine.The magneto-mechanical degradation data of NdFeB at different positions and different times is extracted and analyzed.The results show that the most serious degradation occurs in the inner ring of the rightmost permanent magnet,and the maximum demagnetization is 0.1668T.This study not only gives effective guidance for the use of the electromagnetic brake,but also provides an important theoretical support for the application of NdFeB materials in other impact environments.

Key words: NdFeB, electromagnetic brake, impact environment, magneto-mechanical degradation

CLC Number:

TJ301

LI Lei, YANG Guolai. The Magneto-mechanical Evolution and Degradation of NdFeB Alloys in Launch Environment[J]. Acta Armamentarii, 2025, 46(11): 250205-.

Figures/Tables 17

References 29

[1]	孙正平, 杨国来, 李雷, 等. 火炮电涡流制退机用钕铁硼的热退磁特性[J]. 兵工学报, 2024, 45(8):2712-2727. doi: 10.12382/bgxb.2023.0616
	SUN Z P, YANG G L, LI L, et al. Thermal demagnetization characteristics of Nd-Fe-B used in eddy current recoil mechanism of artillery[J]. Acta Armamentarii, 2024, 45(8):2712-2727. (in Chinese) doi: 10.12382/bgxb.2023.0616
[2]	LI L, WANG L Q, YANG G L. Magnetomechanical degradation of sintered NdFeB induced by impact in eddy current recoil brake[J]. Journal of Magnetism and Magnetic Materials, 2022, 564:170114. doi: 10.1016/j.jmmm.2022.170114 URL
[3]	LI L, WANG L Q, YANG G L, et al. Mechanical and magnetic responses of sintered NdFeB under impact[J]. Journal of Alloys and Compounds, 2022, 910:164951. doi: 10.1016/j.jallcom.2022.164951 URL
[4]	ZHENG X Y, WANG L Q, YANG G L, et al. Phase-field simulation for the mechanical and fracture properties of NdFeB under quasi-static loading conditions[J]. Applied Mathematical Modelling, 2025, 141:115944. doi: 10.1016/j.apm.2025.115944 URL
[5]	LOEFFLER C M, SONG B, LAYRSEN C M, et al. Dynamic compressive behavior of NdFeB rare earth magnets[J]. Journal of Dynamic Behavior of Materials, 2024, 10(2):160-169. doi: 10.1007/s40870-023-00385-8
[6]	李安华, 张月明. 烧结Nd-Fe-B磁体的力学性能研究进展及前景展望[J]. 金属功能材料, 2016, 23(2):1-9. doi: 10.13228/j.boyuan.issn1005-8192.2016012
	LI A H, ZHANG Y M. Research progress and development tendency of mechanical properties of sintered Nd-Fe-B magnets[J]. Metallic Functional Materials, 2016, 23(2):1-9. (in Chinese)
[7]	LI X Q, NI J J, WANG Z W, et al. Electrochemical corrosion behavior of hot-deformed NdFeB magnet with different content of nano-TiC[J]. Journal of Alloys and Compounds, 2022, 917:165518. doi: 10.1016/j.jallcom.2022.165518 URL
[8]	EHELIYAGODA D, VELURI B, LIU G, et al. Unveiling the multiregional circular economy pathways for global dysprosium constraints[J]. Resources Conservation and Recycling, 2025, 215:108121. doi: 10.1016/j.resconrec.2024.108121 URL
[9]	徐俊, 查善顺, 雷燕, 等. Pr基合金晶界扩散对烧结钕铁硼性能和结构的影响[J]. 金属功能材料, 2024, 31(6):84-90.
	XU J, ZHA S S, LEI Y, et al. Effect of grain boundary diffusion of Pr-based alloy on the properties and structure of sintered NdFeB[J]. Metallic Functional Materials, 2024, 31(6):84-90. (in Chinese)
[10]	LEICH L, ROTTGER A, THEISEN W, et al. Densification of nanocrystalline NdFeB magnets processed by electro-discharge sintering-Microstructure,magnetic,and mechanical properties[J]. Journal of Magnetism and Magnetic Materials, 2018, 460:454-460. doi: 10.1016/j.jmmm.2018.04.035 URL
[11]	CAO S, BAO X Q, LI J H, et al. High orientation Nd-Fe-B sintered magnets prepared by wet pressing method[J]. Journal of Magnetism and Magnetic Materials, 2020, 495:165826. doi: 10.1016/j.jmmm.2019.165826 URL
[12]	LUO S G, YANG M N, ZHONG S W, et al. Utility and influence mechanism of densification modulation on grain boundary diffusion in NdFeB magnets[J]. Journal of Rare Earths, 2025, 43(3):569-577. doi: 10.1016/j.jre.2024.02.011 URL
[13]	WANG H R, REN C Y, WAN Y, et al. Experimental study on fracture process of sintered Nd-Fe-B magnets during dynamic Brazilian tests[J]. Journal of Magnetism and Magnetic Materials, 2019, 471:200-208. doi: 10.1016/j.jmmm.2018.09.083 URL
[14]	WANG H R, WAN Y, CHEN D N, et al. Dynamic fracture of sintered Nd-Fe-B magnet under uniaxial compression[J]. Journal of Magnetism and Magnetic Materials, 2018, 456:358-367. doi: 10.1016/j.jmmm.2018.02.058 URL
[15]	WANG H R, ZHANG W C, WAN Y, et al. Study on equation of state and spall strength of sintered Nd-Fe-B magnets[J]. Journal of Magnetism and Magnetic Materials, 2020, 497:166014. doi: 10.1016/j.jmmm.2019.166014 URL
[16]	LI L, YANG G L, WANG L Q, et al. Experimental and theoretical model study on the dynamic mechanical behavior of sintered NdFeB[J]. Journal of Alloys and Compounds, 2022, 890:161787. doi: 10.1016/j.jallcom.2021.161787 URL
[17]	YAO Y W, LI L, WANG L Q, et al. Magneto-mechanical properties of sintered NdFeB under impact load:impact-induced demagnetization experiment,constitutive model and micromagnetic simulation[J]. Journal of Alloys and Compounds, 2024, 987:174134. doi: 10.1016/j.jallcom.2024.174134 URL
[18]	SHKURATOV S I, TALANTSEV E F, BAIRD J, et al. Completely explosive autonomous high-voltage pulsed-power system based on shockwave ferromagnetic primary power source and spiral vector inversion generator[J]. IEEE Transactions on Plasma Science, 2006, 34(5):1866-1872. doi: 10.1109/TPS.2006.883347 URL
[19]	LI Y F, ZHU M G, LI W, et al. The impact induced demagnetization mechanism in NdFeB permanent magnets[J]. Chinese Physics Letters, 2013, 30(9):097501. doi: 10.1088/0256-307X/30/9/097501 URL
[20]	LU F, XU S, WANG L H. Pressure-induced magnetic transition in Nd2Fe14B based on two-sublattice model[J]. Rare Metals, 2022, 41(1):232-239. doi: 10.1007/s12598-018-1192-x URL
[21]	SHI P P, JIN K, ZHENG X J. A general nonlinear magnetomechanical model for ferromagnetic materials under a constant weak magnetic field[J]. Journal of Applied Physics, 2016, 119(14):145103. doi: 10.1063/1.4945766 URL
[22]	KIM S, YUN K C, KIM K H, et al. A general nonlinear magneto-elastic coupled constitutive model for soft ferromagnetic materials[J]. Journal of Magnetism and Magnetic Materials, 2020, 500:166406. doi: 10.1016/j.jmmm.2020.166406 URL
[23]	KIM S, KIM K H, RI D S, et al. A magneto-mechanical model for the magnetic non-destructive evaluation of ferromagnetic materials[J]. Journal of Magnetism and Magnetic Materials, 2023, 570:170539. doi: 10.1016/j.jmmm.2023.170539 URL
[24]	时朋朋. 铁磁材料应力和缺陷的微磁检测定量化研究[D]. 西安: 西安电子科技大学, 2017.
	SHI P P. Quantitative study of micro-magnetic nondestructive testing for stress and defectect in ferromagnetic materials[D]. Xi’an: Xidian University, 2017. (in Chinese)
[25]	XU X, GAO S Q, ZHANG D M, et al. Mechanical behavior of liquid nitrile rubber-modified epoxy resin:experiments,constitutive model and application[J]. International Journal of Mechanical Sciences, 2019, 151:46-60. doi: 10.1016/j.ijmecsci.2018.11.003 URL
[26]	SHI P P, JIN K, ZHENG X J. A magnetomechanical model for the magnetic memory method[J]. International Journal of Mechanical Sciences, 2017, 124:229-241.
[27]	CRAIK D J, WOOD M J. Magnetization changes induced by stress in a constant applied field[J]. Journal of Physics D:Applied Physics, 1970, 3(7):1009. doi: 10.1088/0022-3727/3/7/303 URL
[28]	JILES D C. Theory of the magnetomechanical effect[J]. Journal of Physics D:Applied Physics, 1995, 28(8):1537. doi: 10.1088/0022-3727/28/8/001 URL
[29]	ZHOU H M, ZHOU Y H, ZHENG X J. A general theoretical model of magnetostrictive constitutive relationships for soft ferromagnetic material rods[J]. Journal of Applied Physics, 2008, 104(2):023907. doi: 10.1063/1.2957075 URL

应变	应力/MPa
应变	200s^-1	700s^-1	1200s^-1	1500s^-1
0.005	132.3	209.4	360.8	470.0
0.010	154.0	195.7	351.7	421.5
0.015	147.9	202.5	340.5	315.8
0.020	127.4	185.9	354.6	239.9
0.025	100.5	184.2	366.3	170.5
0.030	66.0	170.4	349.7	132.0
0.035	25.5	188.6	241.8	117.1
0.040			114.9	90.2
0.045				78.8
0.050				64.8
0.055				55.1
0.060				33.6

应变	应力/MPa
应变	200s^-1	700s^-1	1200s^-1	1500s^-1
0.005	132.3	209.4	360.8	470.0
0.010	154.0	195.7	351.7	421.5
0.015	147.9	202.5	340.5	315.8
0.020	127.4	185.9	354.6	239.9
0.025	100.5	184.2	366.3	170.5
0.030	66.0	170.4	349.7	132.0
0.035	25.5	188.6	241.8	117.1
0.040			114.9	90.2
0.045				78.8
0.050				64.8
0.055				55.1
0.060				33.6

参数	数值	参数	数值
μ	0.7	α	2
k	3.0×10⁹	M_s/(A·m^-1)	1.17×10⁶
m	1.2	M_ws/(A·m^-1)	6×10⁷
l /μm	5	ξ /Pa	6×10⁴
D_th	0.4	λ_s/ppm	0.012
E₁/GPa	7.325	c	0.1
E₂/GPa	418.1	N_d	2×10^-6
θ₁/μs	0.69	η	1.5×10^-3
		k	0.5

参数	数值	参数	数值
μ	0.7	α	2
k	3.0×10⁹	M_s/(A·m^-1)	1.17×10⁶
m	1.2	M_ws/(A·m^-1)	6×10⁷
l /μm	5	ξ /Pa	6×10⁴
D_th	0.4	λ_s/ppm	0.012
E₁/GPa	7.325	c	0.1
E₂/GPa	418.1	N_d	2×10^-6
θ₁/μs	0.69	η	1.5×10^-3
		k	0.5

时间/s	A点损伤因子	B点损伤因子	C点损伤因子	D点损伤因子
0.005	2.87×10^-07	8.23×10^-06	8.59×10^-05	1.83×10^-04
0.015	1.14×10^-06	2.26×10^-05	2.38×10^-04	5.50×10^-04
0.025	1.92×10^-06	3.07×10^-05	3.20×10^-04	7.48×10^-04
0.035	2.51×10^-06	3.65×10^-05	3.76×10^-04	8.84×10^-04
0.045	3.08×10^-06	4.28×10^-05	4.41×10^-04	0.00104
0.055	3.72×10^-06	4.96×10^-05	5.09×10^-04	0.00121
0.065	4.35×10^-06	5.56×10^-05	5.68×10^-04	0.00135
0.075	4.91×10^-06	6.06×10^-05	6.15×10^-04	0.00146
0.085	5.29×10^-06	6.35×10^-05	6.41×10^-04	0.00153
0.095	5.52×10^-06	6.55×10^-05	6.60×10^-04	0.00157
0.105	5.67×10^-06	6.66×10^-05	6.70×10^-04	0.0016
0.115	5.79×10^-06	6.71×10^-05	6.75×10^-04	0.00161
0.125	5.81×10^-06	6.74×10^-05	6.77×10^-04	0.00162
0.135	5.84×10^-06	6.83×10^-05	6.86×10^-04	0.00163