Recent advancements in electrocatalysis have highlighted the exceptional application value of amorphous electrocatalysts. Withtheir unique atomic configurations, these electrocatalysts exhibit superior catalytic perfo...Recent advancements in electrocatalysis have highlighted the exceptional application value of amorphous electrocatalysts. Withtheir unique atomic configurations, these electrocatalysts exhibit superior catalytic performance compared to that of their crystalline coun-terparts. Transition metal(TM) amorphous ribbon-shaped electrocatalysts have recently emerged as a new frontier in the catalysis field.Dealloying is widely considered a fascinating method for enhancing the electrocatalyst performance. In this review, we comprehensivelyexamine the principles of water electrolysis, discuss the prevalent methods for fabricating ribbon-configured electrocatalysts, and providean overview of amorphous alloys. Furthermore, we discuss binary, ternary, and high-entropy amorphous TM-based electrocatalysts,which satisfy the requirements necessary for effective water electrolysis. We also propose strategies to enhance the activity of amorphousTM-based ribbons, including morphology control, defect engineering, composition optimization, and heterostructure creation in differentelectrolytes. Our focus extends to the latest developments in the design of heterogeneous micro/nanostructures, management of prepara-tion techniques, and synthesis of different compositions. Finally, we address the ongoing challenges and provide a perspective on the fu-ture development of broadly applicable, self-supporting TM ribbon-shaped electrocatalysts.展开更多
In order to demonstrate that light rare-earth(RE)dopants with strong magnetocrystalline anisotropy, whose net moment couples are antiparallel to those of iron, can also induce giant magnetostriction in Gafenol, a ligh...In order to demonstrate that light rare-earth(RE)dopants with strong magnetocrystalline anisotropy, whose net moment couples are antiparallel to those of iron, can also induce giant magnetostriction in Gafenol, a light RE element Sm was selected as the third element to dope into FeGaalloy.(FeGa)Sm(0≤x≤0.42) ribbons were prepared by melt spinning. The increase of the lattice parameters and saturation magnetization indicates that some Sm atoms enter the A2 matrix substitutionally. Doping the FeGaribbons with the light RE Sm element drastically improves the magnetostriction. Perpendicular magnetostriction value of λ=-5*10is achieved in(FeGa)Sm. It is confirmed that the stronger local magnetocrystalline anisotropy induces larger enhanced magnetostrictions. The greatly enhanced magnetostriction is somehow related to the local microstrains induced by the RE dopants. It is likely that the RE-induced defects in the(FeGa)REribbons function in the similar way as the Ga–Ga pair defects in the undoped Fe–Ga alloys.展开更多
The magnetic cooling utilizing magneto-caloric effect is recognized as promising energy efficiency and environmentally friendly technology.Here we report a systematical study on the microstructures,magnetic properties...The magnetic cooling utilizing magneto-caloric effect is recognized as promising energy efficiency and environmentally friendly technology.Here we report a systematical study on the microstructures,magnetic properties and cryogenic magneto-caloric performances of the Gd_(20)Ho_(20)Tm_(20)Cu_(20)Ni_(20)amorphous ribbons.It is found that the ribbons reveal a second-order phase transition and are accompanied by a table-shaped magneto-caloric effect.The calculated magneticentropy-change maximum|ΔSM|,temperature averaged entropy change(i.e.,TEC(10)),and refrigerant capacity reach 13.9 J/kg·K,13.84 J/kg-K and 740 J/kg with magnetic field change of 0-7 T,respectively,indicating that the present Gd_(20)Ho_(20)Tm_(20)Cu_(20)Ni_(20)amorphous ribbons are good candidates for magnetic cooling.展开更多
The effect of wheel speed on phase formation and magnetic properties of （Ndo.4La0.6）lsFeTzsBzs and （Ndo.4La0.6）13.4Fe79.9B6.7 ribbons prepared by melt-spinning method was investigated experimentally. Based on X-ra...The effect of wheel speed on phase formation and magnetic properties of （Ndo.4La0.6）lsFeTzsBzs and （Ndo.4La0.6）13.4Fe79.9B6.7 ribbons prepared by melt-spinning method was investigated experimentally. Based on X-ray diffraction results, all melt-spun ribbons consist of the main phase with the tetragonal 2：14：1 type structure and the minor α-Fe phase. Magnetic measurements show the maximum magnetic energy product （（BH）max） and the remanence （Mr） increases firstly and then decreases with the increase of wheel speed, while the coercivity （Hci） increases, resulting from the variation of the average volume fraction of the ^-Fe phase and the average grain size in the melt-spun ribbons. Using Henkel plots, the interaction between the 2：14：1 phase and the ^-Fe phase in the melt-spun ribbons was analyzed and the intergranular exchange coupling is manifested. Optimal magnetic properties of Hci - 7.27 kOe, Mr - 90.94 emu/g and （BH）max -- 12.10 MGOe are achieved in the （Ndo.4La0.6）lsFeTzsBT.s ribbon with the wheel speed of 26 m/s. It indicates that magnetic properties of Nd-Fe-B melt-spun ribbons with highly abundant rare earth element La can be improved by optimizing alloy composition and preparation process.展开更多
Flat Steel Ribbon Wound Pressure Vessels (FSRWPVs) are used in many important industry areas. There is no such kind of pressure vessel exploding on operation for its reasonable structure design. Many explosion experim...Flat Steel Ribbon Wound Pressure Vessels (FSRWPVs) are used in many important industry areas. There is no such kind of pressure vessel exploding on operation for its reasonable structure design. Many explosion experiments on Flat Steel Ribbon Wound Pressure Vessel showed that their limited load pressure is related to the winding angle of the steel ribbons. FSRWPVs with reasonable winding angle have better security and lower cost. Reasonable angels given at the end of this paper facilitate engineering design.展开更多
The structure and magnetic hysteresis properties of the cast Sm_(1-x)Zr_(x)(Fe_(0.92)Ti_(0.08))_(10)(x=0-0.3)alloys and melt-spun ribbons prepared from them were studied.In the cast alloy with x>0.2,a considerable ...The structure and magnetic hysteresis properties of the cast Sm_(1-x)Zr_(x)(Fe_(0.92)Ti_(0.08))_(10)(x=0-0.3)alloys and melt-spun ribbons prepared from them were studied.In the cast alloy with x>0.2,a considerable amount of the eutectic phase is found in the SEM micrographs.Analysis of the temperature dependences of the magnetic susceptibility and XRD patterns allows amorphous state in the as-spun ribbons with x>0.2 to be determined.The specific magnetization measured in a field of 17 kOe and remanence decrease with increasing annealing temperature from 800 to 900℃and weakly depend on Zr concentration.The maximal value of coercivity H_(c)=4.7 kOe is obtained on the ribbons with x=0.2 after annealing at 850℃for 10 min.After additional hydrogenation of the ribbons,both the coercivity and remanence increase by 54%and 7%,respectively.展开更多
Committed to obtaining cost-effective NdFeB based permanent magnets,Nd_(27-x)La_(3)Y_(x)Fe_(bal)Al_(0.1)Cu_(0.1)B_(1)(x=0-3)alloys were fabricated to detect the magnetic properties and microstructure.When x=1.8,coerci...Committed to obtaining cost-effective NdFeB based permanent magnets,Nd_(27-x)La_(3)Y_(x)Fe_(bal)Al_(0.1)Cu_(0.1)B_(1)(x=0-3)alloys were fabricated to detect the magnetic properties and microstructure.When x=1.8,coercivity of 1004 kA/m and the magnetic remanence of 0.75 T are obtained,which are close to those of the original Nd_(30)Fe_(bal)A_(l0.1)Cu_(0.1)B_(1)alloy ribbons.The temperature coefficient of coercivity(β)and the temperature coefficient of remanence(α)of the LaY-substituted alloys are better than those of the original alloys.The research results manifest that La is mainly distributed in the grain boundary phases and plays the role of refining the main grains,optimizing the grain boundary phases and improving the wettability between the main phases and the grain boundary phases,while Y tends to enrich in the main phases and enhances the short-range exchange coupling.展开更多
ErNi2 ribbons were produced by rapid solidification using the melt spinning technique.Their structural,magnetic and magnetocaloric properties in the as-solidified state were studied by X-ray diffraction,scanning elect...ErNi2 ribbons were produced by rapid solidification using the melt spinning technique.Their structural,magnetic and magnetocaloric properties in the as-solidified state were studied by X-ray diffraction,scanning electron microscopy,magnetization and specific heat measurements.Samples are single phase with the MgCu2-type crystal structure,a Curie temperature TC of 6.8 K and a saturation magnetization at2 K and 5 T of 124.0 A·m2/kg.For a magnetic field change μ0△H of 5 T(2 T) ribbons show a maximum magnetic entropy change |△SMpeak| of 24.1(16.9) J/(kg·K),and an adiabatic temperature change △Tadmax of8.1(4.4) K;this is similar to the previously reported literature for bulk alloys that were processed through conventional melting techniques followed by prolonged thermal annealing.In addition,the samples also show slightly wider △SM(T) curves with respect to bulk alloys leading to a larger refrigerant capacity.展开更多
Amorphous （Nd,Pr）13Fe80Nb1B6 ribbons were crystallized at 670-730°C for 5-25 min to study the effects of isothermal crystallization on their behavior and magnetic properties. XRD results indicate that the isoth...Amorphous （Nd,Pr）13Fe80Nb1B6 ribbons were crystallized at 670-730°C for 5-25 min to study the effects of isothermal crystallization on their behavior and magnetic properties. XRD results indicate that the isothermal incubation time is 12, 5, and less than 5 min at 670, 700, and 730°C, respectively. High coercivities, with the maximum value of iHc = 1616 kA/m at 700°C for 19 min, measured by a physical property measurement system, are obtained in the crystallized ribbons. This is mainly attributed to the addition of Pr and Nb, because Pr2Fe14B has a higher anisotropic field than Nd2Fe14B, and Nb enriched in the grain boundary regions can not only reduce the exchange-coupling effects among hard grains, but also impede grain growth during the crystallization process. In addition, it should also be related to the characteristics of the furnace that the authors designed.展开更多
The total ribbon voltage of as-quenched and annealed Fe96-xZr_xB_4 (x=7 or 10) ribbons has been measured as a function of applied dc field and drive current frequency. The experimental results show that both samples e...The total ribbon voltage of as-quenched and annealed Fe96-xZr_xB_4 (x=7 or 10) ribbons has been measured as a function of applied dc field and drive current frequency. The experimental results show that both samples exist the optimum annealing temperature and optimum frequency at which the relative change in ribbon voltage is strongest, and the sensitivity of the magnetic response of the annealed Fe_89Zr_7B_4 ribbon is two order of magnitude larger than that of the annealed Fe_86Zr_10 B4 ribbon. The effect of magnetic properties and structural characteristics on giant magneto-impedance was discussed.展开更多
We theoretically and numerically demonstrate that a transmission-type electrically tunable polarizer can be realized by using graphene ribbons supported on a dielectric film with a graphene sheet behind. The polarizat...We theoretically and numerically demonstrate that a transmission-type electrically tunable polarizer can be realized by using graphene ribbons supported on a dielectric film with a graphene sheet behind. The polarization mechanism originates from the antenna plasmon resonance of graphene stripes. The results of full-wave numerical simulations reveal that transmittance of 0.70 for one polarization and 0.0073 for another polarization can be obtained at normal incidence. The transmission-type electrically tunable polarizer provides and facilitates a variety of applications, including filtering, detecting, and imaging.展开更多
A set of stacked ribbons with the composition of Fe77Ga23 were prepared with different wheel velocities of 7 m/s, 12.5 m/s and 25 m/s（named as S7, S12.5 and S25, respectively）. High resolution X-ray diffraction patt...A set of stacked ribbons with the composition of Fe77Ga23 were prepared with different wheel velocities of 7 m/s, 12.5 m/s and 25 m/s（named as S7, S12.5 and S25, respectively）. High resolution X-ray diffraction patterns of these ribbons show that all the ribbons present the disordered A2 structure, whereas an additional modified-DO3 phase is detected in S12.5 and S25. S25 has stronger（100） texture than other two samples. Ga K-edge extended X-ray absorption fine structure results indicate that both bond distance and the number of Ga atoms in the second neighbor shell around Ga decrease with increasing wheel velocity. No Ga cluster is detected in the studied ribbons. A short-range ordering Ga-rich phase and large local strain have no obvious influence on magnetostriction of S7. It is believed that both the（100） texture and the additional modified-DO3 phase play a positive role in magnetostrictive properties of Fe77Ga23 ribbons.展开更多
This study reports the stabilization of the RFe12-type based compounds where part of R and Fe are substituted with Zr and Co and Si, respectively, in order to examine whether these rare-earth-lean materials are suitab...This study reports the stabilization of the RFe12-type based compounds where part of R and Fe are substituted with Zr and Co and Si, respectively, in order to examine whether these rare-earth-lean materials are suitable for applications as permanent magnets. Structural and magnetic characterization of the family of alloys with the general formula Nd0.4 Zr0.6 Fe10-xCoxSi2(x = 0 -3) and their melt-spun ribbons were carried out using X-ray diffraction and M€ossbauer spectroscopy. The ThMn12-type structure is obtained for all samples as the majority phase with a minority a-Fe(CoSi) phase(less than 5 wt%) as it was estimated by XRD for x = 1 and 2. The Curie temperature increases linearly with Co substitution from 561 K for x = 0 to 712 K for x = 3. The saturation magnetization decreases slightly from 130.5(x =1)to 129.1 A·m2/kg(x=3), while the anisotropy field is following the same trend.展开更多
The nanocrystalline magnetic ribbons of(Nd_(1-x)Y_(x))_(14.5)Fe_(ba1)B(6)Co_(0.2)Al_(1)Cu_(0.15)(x=0,0.1,0.2,0.3,0.4) were prepared by melt-spinning technique.The magnetic properties and microstructures were systemati...The nanocrystalline magnetic ribbons of(Nd_(1-x)Y_(x))_(14.5)Fe_(ba1)B(6)Co_(0.2)Al_(1)Cu_(0.15)(x=0,0.1,0.2,0.3,0.4) were prepared by melt-spinning technique.The magnetic properties and microstructures were systematically investigated for the ribbons.It is found that Y substituting Nd in the R_(2)Fe_(14)B main phase grains gives rise to the decrease in the crystal lattice constant.When Y content increases from x=0 to x=0.4,the remanence and intrinsic coercivity(H_(cj)) decrease from 0.80 to 0.71 T and1400 to 809 kA·m^(-)1,respectively,with the corresponding descent rate of 11.5% and 42.5%.It is impressed that the average grain size increases with Y content increasing.And the strong intergrain exchange coupling interactions exist in all the ribbons and could be enhanced with an appropriate Y substitution,such as x=0.4.Moreover,magnetization reversal mechanism is confirmed to be pinning type for the ribbons.The results provide valuable reference to the fabrication of Y-substituted Nd-Y-Fe-B sintered magnets.展开更多
The crystal structure,martensitic transformation and magnetocaloric effect have been studied in all-d-metal Ni35Co15Mn33Fe2Ti15alloy ribbons with different wheel speeds(15 m/s(S15),30 m/s(S30),and 45 m/s(S45)).All thr...The crystal structure,martensitic transformation and magnetocaloric effect have been studied in all-d-metal Ni35Co15Mn33Fe2Ti15alloy ribbons with different wheel speeds(15 m/s(S15),30 m/s(S30),and 45 m/s(S45)).All three ribbons crystalize in B2-ordered structure at room temperature with crystal constants of 5.893(2)A,5.898(4)A,and5.898(6)A,respectively.With the increase of wheel speed,the martensitic transformation temperature decreases from230 K to 210 K,the Curie temperature increases slightly from 371 K to 378 K.At the same time,magnetic entropy change(△Sm)is also enhanced,as well as refrigeration capacity(RC).The maximum△Sm of 15.6(39.7)J/kg·K and RC of85.5(212.7)J/kg under?H=20(50)k Oe(1 Oe=79.5775 A·m^(-1))appear in S45.The results indicate that the ribbons could be the candidate for solid-state magnetic refrigeration materials.展开更多
The giant magneto-impedance (GMI) effect associated with the variation of transverse permeability for the ribbons Fe89Zr6Hf1B4 with different annealing temperatures T-A = 793, 823, 893, 923, 993, and 1033 K was invest...The giant magneto-impedance (GMI) effect associated with the variation of transverse permeability for the ribbons Fe89Zr6Hf1B4 with different annealing temperatures T-A = 793, 823, 893, 923, 993, and 1033 K was investigated. There is an optimum annealing temperature TA = 993 K for obtaining the largest GMI effect for the ribbons Fe89Zr6Hf1B4. The magneto-impedance GMI (Z) = (Z(H) - Z(0))/Z(0) for the ribbon with T-A = 993 K can reach -55.09% at a frequency f = 900 kHz under H = 7162 A/m. The relative changes of the real part of transverse permeability Delta mu'/mu'(0) = (mu'(H)- mu'(0))/mu'(0) under H = 7162 A center dot m(-1) at f = 1 MHz are -78.83%, -89.98% and -94.77 % for Fe89Zr6Hf1B4 ribbons with T-A = 823, 893, and 993 K, respectively. The strong GMI effect is accompanied by the large change of transverse permeability. A large magnetoreaetance GMI(X) = (X (H) - X (0))/X (0) of -81.09% can be obtained at f = 100 kHz under H = 7162 A/m for the ribbon with T-A = 993 K. Meanwhile, this present result gave an experimental support to the previous concept / assumption that the positive peak in the field dependence of magneto-impedance is connected to the peak of transverse permeability with varying fields.展开更多
Ms-T curves and hysteresis loops were investigated for amorphous Fe78Si9B13, (FeNi)78(CrSiB)22, their lap-wound-cores, and their composite ribbons made by two-chamber-crucible technique. The properties of the lap-woun...Ms-T curves and hysteresis loops were investigated for amorphous Fe78Si9B13, (FeNi)78(CrSiB)22, their lap-wound-cores, and their composite ribbons made by two-chamber-crucible technique. The properties of the lap-wound cores of the two kinds of ribbons are similar. For the composite ribbons, the intrinsic properties are the average of the two alloys. Their technological properties, i.e., hysteresis loops, however, are no longer the average of the two alloys. Instead, they show some dramatic changes compared to the lap-wound-cores. Especially, the shape of the hysteresis loop of the composite ribbon cores is largely different from that of lap-wound-cores. The reason for the difference is supposed to be internal stress induced from cooling after annealing.展开更多
The dipolar interactions are investigated through the asymmetric magneto-impedance in FINEMET/SiO_(2)/FePd composite ribbons.The interface between the hard(FePd layer)phase and soft(FINEMET ribbon)phase is coherent by...The dipolar interactions are investigated through the asymmetric magneto-impedance in FINEMET/SiO_(2)/FePd composite ribbons.The interface between the hard(FePd layer)phase and soft(FINEMET ribbon)phase is coherent by SiO_(2)layer in FINEMET/SiO_(2)/FePd composite ribbons,which effectively induces dipolar interactions.The contribution of dipolar interaction to the bias field(Hb)by asymmetrical giant magneto-impedance and magnetic properties is analyzed.The results show that Hb response decreases with the increase of the SiO_(2)layer thickness,indicating that the linear region near-zero field can be tuned by the thickness of SiO_(2)layer.These results allow the GMI ratio(58%)and characteristic frequency(500 kHz)to be optimized.The transverse and longitudinal magnetic domain structures of FINEMET ribbon and FePd film are confirmed,respectively.The composite ribbons with high GMI ratio and low frequency can be applied to linear magnetic sensors.展开更多
The giant magnetoimpedance(GMI)effect in as-quenchedFe_89-xZr_7B_4Cu_x(x=1.0-2.5)ribbons is reported. The as-quenchedFe_89-xZr_7B_4Cu_x(x=1.0-2.5)ribbons were prepared by the vacuummelt-spun processes with the quenchi...The giant magnetoimpedance(GMI)effect in as-quenchedFe_89-xZr_7B_4Cu_x(x=1.0-2.5)ribbons is reported. The as-quenchedFe_89-xZr_7B_4Cu_x(x=1.0-2.5)ribbons were prepared by the vacuummelt-spun processes with the quenching speed of 37 m/s. The magne-Toimpedance measurement were performance at room temperature, wherethe current flow through the length of the ribbons in the directionParallel to the dc fields. results show that values Z(impedance),R(resistance)for both H = 0 A/m and H = 5 127 A/m Increases withincreasing ac frequency. This can be explained by the skin effectmechanism.展开更多
U.S. Department of Commerce’s final ruling finally made one-year long "double anti-" investigation (anti-dumping and anti-subsidy) in the made-in-China narrow ribbons come to a settlement on July 13th Washi...U.S. Department of Commerce’s final ruling finally made one-year long "double anti-" investigation (anti-dumping and anti-subsidy) in the made-in-China narrow ribbons come to a settlement on July 13th Washington time.展开更多
基金financially supported by the Yancheng Polytechnic College School-Level Scientific Research, China (No. ygy1903)the National Natural Science Foundation of China (Nos. 52001163, 52075237, and 52371157)+2 种基金the Open Project of Taihu Laboratory of Deep-Sea Technology Science, Key Research and Development Plan of Jiangsu Province, China (No. BE2019119)supported by the Priority Academic Program Development of Jiangsu Higher Education Institution (PAPD), Chinathe research funding for the Jiangsu Specially-Appointed Professor Program, China。
文摘Recent advancements in electrocatalysis have highlighted the exceptional application value of amorphous electrocatalysts. Withtheir unique atomic configurations, these electrocatalysts exhibit superior catalytic performance compared to that of their crystalline coun-terparts. Transition metal(TM) amorphous ribbon-shaped electrocatalysts have recently emerged as a new frontier in the catalysis field.Dealloying is widely considered a fascinating method for enhancing the electrocatalyst performance. In this review, we comprehensivelyexamine the principles of water electrolysis, discuss the prevalent methods for fabricating ribbon-configured electrocatalysts, and providean overview of amorphous alloys. Furthermore, we discuss binary, ternary, and high-entropy amorphous TM-based electrocatalysts,which satisfy the requirements necessary for effective water electrolysis. We also propose strategies to enhance the activity of amorphousTM-based ribbons, including morphology control, defect engineering, composition optimization, and heterostructure creation in differentelectrolytes. Our focus extends to the latest developments in the design of heterogeneous micro/nanostructures, management of prepara-tion techniques, and synthesis of different compositions. Finally, we address the ongoing challenges and provide a perspective on the fu-ture development of broadly applicable, self-supporting TM ribbon-shaped electrocatalysts.
基金financially supported by the National Basic Research Program (No. 2012CB619404)the National High-Tech R&D Program (No. 2013AA030903)the National Natural Science Foundation of China (Nos. 51331001 and 51221163)
文摘In order to demonstrate that light rare-earth(RE)dopants with strong magnetocrystalline anisotropy, whose net moment couples are antiparallel to those of iron, can also induce giant magnetostriction in Gafenol, a light RE element Sm was selected as the third element to dope into FeGaalloy.(FeGa)Sm(0≤x≤0.42) ribbons were prepared by melt spinning. The increase of the lattice parameters and saturation magnetization indicates that some Sm atoms enter the A2 matrix substitutionally. Doping the FeGaribbons with the light RE Sm element drastically improves the magnetostriction. Perpendicular magnetostriction value of λ=-5*10is achieved in(FeGa)Sm. It is confirmed that the stronger local magnetocrystalline anisotropy induces larger enhanced magnetostrictions. The greatly enhanced magnetostriction is somehow related to the local microstrains induced by the RE dopants. It is likely that the RE-induced defects in the(FeGa)REribbons function in the similar way as the Ga–Ga pair defects in the undoped Fe–Ga alloys.
基金Project supported by the National Natural Science Foundation of China(Grant No.52071197)the Science and Technology Committee of Shanghai(Grant No.19ZR1418300)+2 种基金the Independent Research and Development Project of State Key Laboratory of Advanced Special SteelShanghai Key Laboratory of Advanced Ferrometallurgy,Shanghai University(Grant No.SKLASS 2019-Z003)the Science and Technology Commission of Shanghai Municipality(Grant No.19DZ2270200)。
文摘The magnetic cooling utilizing magneto-caloric effect is recognized as promising energy efficiency and environmentally friendly technology.Here we report a systematical study on the microstructures,magnetic properties and cryogenic magneto-caloric performances of the Gd_(20)Ho_(20)Tm_(20)Cu_(20)Ni_(20)amorphous ribbons.It is found that the ribbons reveal a second-order phase transition and are accompanied by a table-shaped magneto-caloric effect.The calculated magneticentropy-change maximum|ΔSM|,temperature averaged entropy change(i.e.,TEC(10)),and refrigerant capacity reach 13.9 J/kg·K,13.84 J/kg-K and 740 J/kg with magnetic field change of 0-7 T,respectively,indicating that the present Gd_(20)Ho_(20)Tm_(20)Cu_(20)Ni_(20)amorphous ribbons are good candidates for magnetic cooling.
基金Project supported by the National Basic Research Program of China(973 Program)(2014CB643703)the National Key Research and Development Program of China(2016YFB0700901)+1 种基金the National Natural Science Foundation of China(51761008,51461013)the Guangxi Natural Science Foundation(2016GXNSFDA380015,2016GXNSFGA380001)
文摘The effect of wheel speed on phase formation and magnetic properties of （Ndo.4La0.6）lsFeTzsBzs and （Ndo.4La0.6）13.4Fe79.9B6.7 ribbons prepared by melt-spinning method was investigated experimentally. Based on X-ray diffraction results, all melt-spun ribbons consist of the main phase with the tetragonal 2：14：1 type structure and the minor α-Fe phase. Magnetic measurements show the maximum magnetic energy product （（BH）max） and the remanence （Mr） increases firstly and then decreases with the increase of wheel speed, while the coercivity （Hci） increases, resulting from the variation of the average volume fraction of the ^-Fe phase and the average grain size in the melt-spun ribbons. Using Henkel plots, the interaction between the 2：14：1 phase and the ^-Fe phase in the melt-spun ribbons was analyzed and the intergranular exchange coupling is manifested. Optimal magnetic properties of Hci - 7.27 kOe, Mr - 90.94 emu/g and （BH）max -- 12.10 MGOe are achieved in the （Ndo.4La0.6）lsFeTzsBT.s ribbon with the wheel speed of 26 m/s. It indicates that magnetic properties of Nd-Fe-B melt-spun ribbons with highly abundant rare earth element La can be improved by optimizing alloy composition and preparation process.
文摘Flat Steel Ribbon Wound Pressure Vessels (FSRWPVs) are used in many important industry areas. There is no such kind of pressure vessel exploding on operation for its reasonable structure design. Many explosion experiments on Flat Steel Ribbon Wound Pressure Vessel showed that their limited load pressure is related to the winding angle of the steel ribbons. FSRWPVs with reasonable winding angle have better security and lower cost. Reasonable angels given at the end of this paper facilitate engineering design.
基金Project supported by BRICS STI Framework Program for Basic Research(RFFI-BRICS)(17-52-80072)NSFC-BRICS(51761145026)the State Assignment of Ministry of Education and Science of the Russian Federation(topic“Magnet”)(AAAA-A18-118020290129-5)
文摘The structure and magnetic hysteresis properties of the cast Sm_(1-x)Zr_(x)(Fe_(0.92)Ti_(0.08))_(10)(x=0-0.3)alloys and melt-spun ribbons prepared from them were studied.In the cast alloy with x>0.2,a considerable amount of the eutectic phase is found in the SEM micrographs.Analysis of the temperature dependences of the magnetic susceptibility and XRD patterns allows amorphous state in the as-spun ribbons with x>0.2 to be determined.The specific magnetization measured in a field of 17 kOe and remanence decrease with increasing annealing temperature from 800 to 900℃and weakly depend on Zr concentration.The maximal value of coercivity H_(c)=4.7 kOe is obtained on the ribbons with x=0.2 after annealing at 850℃for 10 min.After additional hydrogenation of the ribbons,both the coercivity and remanence increase by 54%and 7%,respectively.
基金Project supported by the National Natural Science Foundation of China(51901089,52061015)China Postdoctoral Science Foundation(2020M682064)+3 种基金Young Elite Scientists Sponsorship Program by CAST(YESS20200250)the Key Research and Development Program of Jiangxi Province(20201BBE51010)Postdoctoral Science Foundation of Jiangxi Province(2020KY19)the Program of Qingjiang Excellent Young Talents of Jiangxi University of Science and Technology(JXUSTQJYX2020003)。
文摘Committed to obtaining cost-effective NdFeB based permanent magnets,Nd_(27-x)La_(3)Y_(x)Fe_(bal)Al_(0.1)Cu_(0.1)B_(1)(x=0-3)alloys were fabricated to detect the magnetic properties and microstructure.When x=1.8,coercivity of 1004 kA/m and the magnetic remanence of 0.75 T are obtained,which are close to those of the original Nd_(30)Fe_(bal)A_(l0.1)Cu_(0.1)B_(1)alloy ribbons.The temperature coefficient of coercivity(β)and the temperature coefficient of remanence(α)of the LaY-substituted alloys are better than those of the original alloys.The research results manifest that La is mainly distributed in the grain boundary phases and plays the role of refining the main grains,optimizing the grain boundary phases and improving the wettability between the main phases and the grain boundary phases,while Y tends to enrich in the main phases and enhances the short-range exchange coupling.
基金the SEP-CONACYT,Mexico(A1-S-37066)the MINECO,Spain(MAT2014-56116-C4-R)Principado de Asturias,Spain(IDI/2018/000185)。
文摘ErNi2 ribbons were produced by rapid solidification using the melt spinning technique.Their structural,magnetic and magnetocaloric properties in the as-solidified state were studied by X-ray diffraction,scanning electron microscopy,magnetization and specific heat measurements.Samples are single phase with the MgCu2-type crystal structure,a Curie temperature TC of 6.8 K and a saturation magnetization at2 K and 5 T of 124.0 A·m2/kg.For a magnetic field change μ0△H of 5 T(2 T) ribbons show a maximum magnetic entropy change |△SMpeak| of 24.1(16.9) J/(kg·K),and an adiabatic temperature change △Tadmax of8.1(4.4) K;this is similar to the previously reported literature for bulk alloys that were processed through conventional melting techniques followed by prolonged thermal annealing.In addition,the samples also show slightly wider △SM(T) curves with respect to bulk alloys leading to a larger refrigerant capacity.
基金supported by the National Natural Science Foundation of China (No. 50744014)the National Basic Research Foundation (No. 2004CCA04000)+3 种基金Science and Technology Department of Zhejiang Province (Nos. 2008C21046 and 2008C11086-1)the Natural Science Foundation of Zhejiang Province,China (No. Y406389)the Research and Development Program of Ningbo Bureau of Science and Technology (No. 2006B100054)K.C.Wong Magna Found in Ningbo University
文摘Amorphous （Nd,Pr）13Fe80Nb1B6 ribbons were crystallized at 670-730°C for 5-25 min to study the effects of isothermal crystallization on their behavior and magnetic properties. XRD results indicate that the isothermal incubation time is 12, 5, and less than 5 min at 670, 700, and 730°C, respectively. High coercivities, with the maximum value of iHc = 1616 kA/m at 700°C for 19 min, measured by a physical property measurement system, are obtained in the crystallized ribbons. This is mainly attributed to the addition of Pr and Nb, because Pr2Fe14B has a higher anisotropic field than Nd2Fe14B, and Nb enriched in the grain boundary regions can not only reduce the exchange-coupling effects among hard grains, but also impede grain growth during the crystallization process. In addition, it should also be related to the characteristics of the furnace that the authors designed.
文摘The total ribbon voltage of as-quenched and annealed Fe96-xZr_xB_4 (x=7 or 10) ribbons has been measured as a function of applied dc field and drive current frequency. The experimental results show that both samples exist the optimum annealing temperature and optimum frequency at which the relative change in ribbon voltage is strongest, and the sensitivity of the magnetic response of the annealed Fe_89Zr_7B_4 ribbon is two order of magnitude larger than that of the annealed Fe_86Zr_10 B4 ribbon. The effect of magnetic properties and structural characteristics on giant magneto-impedance was discussed.
基金Supported by the National Basic Research Program of China under Grant No 2012CB933501the National Natural Science Foundation of China under Grant Nos 61177051,11304389,61404174 and 61205087
文摘We theoretically and numerically demonstrate that a transmission-type electrically tunable polarizer can be realized by using graphene ribbons supported on a dielectric film with a graphene sheet behind. The polarization mechanism originates from the antenna plasmon resonance of graphene stripes. The results of full-wave numerical simulations reveal that transmittance of 0.70 for one polarization and 0.0073 for another polarization can be obtained at normal incidence. The transmission-type electrically tunable polarizer provides and facilitates a variety of applications, including filtering, detecting, and imaging.
基金Projects(11079022,51271093,10904071,U1332106)supported by the National Natural Science Foundation of China
文摘A set of stacked ribbons with the composition of Fe77Ga23 were prepared with different wheel velocities of 7 m/s, 12.5 m/s and 25 m/s（named as S7, S12.5 and S25, respectively）. High resolution X-ray diffraction patterns of these ribbons show that all the ribbons present the disordered A2 structure, whereas an additional modified-DO3 phase is detected in S12.5 and S25. S25 has stronger（100） texture than other two samples. Ga K-edge extended X-ray absorption fine structure results indicate that both bond distance and the number of Ga atoms in the second neighbor shell around Ga decrease with increasing wheel velocity. No Ga cluster is detected in the studied ribbons. A short-range ordering Ga-rich phase and large local strain have no obvious influence on magnetostriction of S7. It is believed that both the（100） texture and the additional modified-DO3 phase play a positive role in magnetostrictive properties of Fe77Ga23 ribbons.
基金partially supported by the Н2020-MSCA-RISE2015 INAPEM: International Network on Advanced High Energy Permanent MagnetsН2020-NMP23-2015 NOVAMAG: Novel Materials by Design for substituting Critical Raw Materialssupported by DOE DE-FG02-90ER45413
文摘This study reports the stabilization of the RFe12-type based compounds where part of R and Fe are substituted with Zr and Co and Si, respectively, in order to examine whether these rare-earth-lean materials are suitable for applications as permanent magnets. Structural and magnetic characterization of the family of alloys with the general formula Nd0.4 Zr0.6 Fe10-xCoxSi2(x = 0 -3) and their melt-spun ribbons were carried out using X-ray diffraction and M€ossbauer spectroscopy. The ThMn12-type structure is obtained for all samples as the majority phase with a minority a-Fe(CoSi) phase(less than 5 wt%) as it was estimated by XRD for x = 1 and 2. The Curie temperature increases linearly with Co substitution from 561 K for x = 0 to 712 K for x = 3. The saturation magnetization decreases slightly from 130.5(x =1)to 129.1 A·m2/kg(x=3), while the anisotropy field is following the same trend.
基金financially supported by the National Basic Research Program of China (No.2014CB643701)the National Natural Science Foundation of China (Nos.51371054 ,51331003)the National Key Research and Development Program of China (No.2016YFB0700903)。
文摘The nanocrystalline magnetic ribbons of(Nd_(1-x)Y_(x))_(14.5)Fe_(ba1)B(6)Co_(0.2)Al_(1)Cu_(0.15)(x=0,0.1,0.2,0.3,0.4) were prepared by melt-spinning technique.The magnetic properties and microstructures were systematically investigated for the ribbons.It is found that Y substituting Nd in the R_(2)Fe_(14)B main phase grains gives rise to the decrease in the crystal lattice constant.When Y content increases from x=0 to x=0.4,the remanence and intrinsic coercivity(H_(cj)) decrease from 0.80 to 0.71 T and1400 to 809 kA·m^(-)1,respectively,with the corresponding descent rate of 11.5% and 42.5%.It is impressed that the average grain size increases with Y content increasing.And the strong intergrain exchange coupling interactions exist in all the ribbons and could be enhanced with an appropriate Y substitution,such as x=0.4.Moreover,magnetization reversal mechanism is confirmed to be pinning type for the ribbons.The results provide valuable reference to the fabrication of Y-substituted Nd-Y-Fe-B sintered magnets.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.52001102 and 51771003)。
文摘The crystal structure,martensitic transformation and magnetocaloric effect have been studied in all-d-metal Ni35Co15Mn33Fe2Ti15alloy ribbons with different wheel speeds(15 m/s(S15),30 m/s(S30),and 45 m/s(S45)).All three ribbons crystalize in B2-ordered structure at room temperature with crystal constants of 5.893(2)A,5.898(4)A,and5.898(6)A,respectively.With the increase of wheel speed,the martensitic transformation temperature decreases from230 K to 210 K,the Curie temperature increases slightly from 371 K to 378 K.At the same time,magnetic entropy change(△Sm)is also enhanced,as well as refrigeration capacity(RC).The maximum△Sm of 15.6(39.7)J/kg·K and RC of85.5(212.7)J/kg under?H=20(50)k Oe(1 Oe=79.5775 A·m^(-1))appear in S45.The results indicate that the ribbons could be the candidate for solid-state magnetic refrigeration materials.
基金This project was financially supported by the National Natural Science Foundation of China (No. 50271036).
文摘The giant magneto-impedance (GMI) effect associated with the variation of transverse permeability for the ribbons Fe89Zr6Hf1B4 with different annealing temperatures T-A = 793, 823, 893, 923, 993, and 1033 K was investigated. There is an optimum annealing temperature TA = 993 K for obtaining the largest GMI effect for the ribbons Fe89Zr6Hf1B4. The magneto-impedance GMI (Z) = (Z(H) - Z(0))/Z(0) for the ribbon with T-A = 993 K can reach -55.09% at a frequency f = 900 kHz under H = 7162 A/m. The relative changes of the real part of transverse permeability Delta mu'/mu'(0) = (mu'(H)- mu'(0))/mu'(0) under H = 7162 A center dot m(-1) at f = 1 MHz are -78.83%, -89.98% and -94.77 % for Fe89Zr6Hf1B4 ribbons with T-A = 823, 893, and 993 K, respectively. The strong GMI effect is accompanied by the large change of transverse permeability. A large magnetoreaetance GMI(X) = (X (H) - X (0))/X (0) of -81.09% can be obtained at f = 100 kHz under H = 7162 A/m for the ribbon with T-A = 993 K. Meanwhile, this present result gave an experimental support to the previous concept / assumption that the positive peak in the field dependence of magneto-impedance is connected to the peak of transverse permeability with varying fields.
文摘Ms-T curves and hysteresis loops were investigated for amorphous Fe78Si9B13, (FeNi)78(CrSiB)22, their lap-wound-cores, and their composite ribbons made by two-chamber-crucible technique. The properties of the lap-wound cores of the two kinds of ribbons are similar. For the composite ribbons, the intrinsic properties are the average of the two alloys. Their technological properties, i.e., hysteresis loops, however, are no longer the average of the two alloys. Instead, they show some dramatic changes compared to the lap-wound-cores. Especially, the shape of the hysteresis loop of the composite ribbon cores is largely different from that of lap-wound-cores. The reason for the difference is supposed to be internal stress induced from cooling after annealing.
基金Project supported by the Natural Science Foundation of Shandong Province,China(Grant No.ZR2022MF276)the Major Innovation Fund of Qilu University of Technology(Shandong Academy of Science),China(Grant No.2022JBZ02-02)+1 种基金the Fund from Shanghai Science and Technology Commission,China(Grant No.22142200900)the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Grant No.2019GXNSFAA245056).
文摘The dipolar interactions are investigated through the asymmetric magneto-impedance in FINEMET/SiO_(2)/FePd composite ribbons.The interface between the hard(FePd layer)phase and soft(FINEMET ribbon)phase is coherent by SiO_(2)layer in FINEMET/SiO_(2)/FePd composite ribbons,which effectively induces dipolar interactions.The contribution of dipolar interaction to the bias field(Hb)by asymmetrical giant magneto-impedance and magnetic properties is analyzed.The results show that Hb response decreases with the increase of the SiO_(2)layer thickness,indicating that the linear region near-zero field can be tuned by the thickness of SiO_(2)layer.These results allow the GMI ratio(58%)and characteristic frequency(500 kHz)to be optimized.The transverse and longitudinal magnetic domain structures of FINEMET ribbon and FePd film are confirmed,respectively.The composite ribbons with high GMI ratio and low frequency can be applied to linear magnetic sensors.
文摘The giant magnetoimpedance(GMI)effect in as-quenchedFe_89-xZr_7B_4Cu_x(x=1.0-2.5)ribbons is reported. The as-quenchedFe_89-xZr_7B_4Cu_x(x=1.0-2.5)ribbons were prepared by the vacuummelt-spun processes with the quenching speed of 37 m/s. The magne-Toimpedance measurement were performance at room temperature, wherethe current flow through the length of the ribbons in the directionParallel to the dc fields. results show that values Z(impedance),R(resistance)for both H = 0 A/m and H = 5 127 A/m Increases withincreasing ac frequency. This can be explained by the skin effectmechanism.
文摘U.S. Department of Commerce’s final ruling finally made one-year long "double anti-" investigation (anti-dumping and anti-subsidy) in the made-in-China narrow ribbons come to a settlement on July 13th Washington time.
