检索结果-南通市图书馆

BREAK-UP MECHANISM OF METAL DROPLETS GENERATED BY AN ELECTROHYDRODYNAMIC TECHNIqUE

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 1997年第1期10卷 39-45页

作者： X.F. Yu z.q. Hu H.S. Hu z jiang and X. Liu(State Key Laboratory of RSA, Institote of Metal Research, Chinese Academy of Sciences, Shenyang110015, China)(Northeastern University Shenyang 110006, China) Inst of Metal Research Chinese Acad of Sciences Shenyang China

Nanometer powders can be produced by an electrohydrodynamic technique. The breakup mechanism of the metal droplets generated by the electrohydrodynamic technique was analysed. It showed that the applied voltage, the electric field Btrength, the properties of the molten metal and the volumetric flow rate of the molten metal directly effect the breat-up extent of the metal droplets.

关键词： electrohydrodynamic technique nanometer powden charged liquid droplet surface charge density

IMPROVEMENT OF CARBIDE MORPHOLOGY ANDMECHANICAL PROPERTIES OF Cr12MoV STEELS

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2000年第5期13卷 1053-1058页

作者： Cui, X.H. jiang, q.C. Wang, S.q. He, z.M. Sch. of Mat. Sci. and Eng. Jilin Univ. of Technol. Changchun 130025 China

Compared with conventional cast Cr12MoV steel and forged Cr12MoV steels, carbide morphology and properties of modified cast Cr12MoV steels were investigated by performing hardness test, impact test, fracture toughness test, fatigue crack propagation test, metallographic examination and quantitatively metallographic analysis. The results indicate that the carbide morphology in modified cast steel is characterized by uniformly-distributed granular carbide, which is different from that of conventional cast steel, but similar to that of forged steel. the impact toughness of modified cast steel is distinctly increased to 12.75 J/cm2 from 6.8 J/cm2 in the conventional cast steel with networked carbide, because of carbide granulation. Furthermore, The fracture toughness and fatigue-crack-propagation threshold of modified cast steel are not only higher than that of the conventional cast steel, but also higher than that of the forged steels.

关键词： Alloys Carbides Mechanical properties Morphology

EFFECT OF MODIFICATION ON CARBIDE GRANULATION AND ITS MECHANISM

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 1999年第2期12卷 167-172页

作者： Wang, S.q. jiang, q.C. Cui, X.H. He, z.M. Jilin Univ of Technology Changchun China

By the modification, network carbide is disconnected at 1100 degree C through uneven dissolution at higher energy places in carbide, where there is twin or lattice distortion, and is granulated at 1130 degree C through element diffusion. The stability of M//7C//3 carbide is decreased because of the modification reducing the segregation of Cr and Mo, thus the temperature, at which uneven dissolution of carbide commenced, is decreased. Also lattice distortion or defect such as twin in carbide is increased by the modification, which prompts widespread disconnections in carbide. In addition, the modification prompts element diffusion to accelerate the kinetics process of carbide granulation. (Edited author abstract) 6 Refs.

关键词： Carbides Chromium alloys Granulation Modification Morphology

Tensile Elastic Behavior of a zr-Cu-Ag-Al Bulk Metallic Glass

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2014年第6期30卷 595-598页

作者： q.P.Cao J.B.Jin q.Yu X.D.Wang D.X.zhang Y.jiang J.z.jiang International Center for New-Structured Materials (ICNSM) State Key Laboratory of Silicon MaterialsDepartment of Materials Science and Engineering Zhejiang University Department of Mechanical Engineering University of Nevada Reno NV 89557 USA State Key Laboratory of Modern Optical Instrumentation Zhejiang University

Tensile elastic behavior of bulk zr46（Cu4.5/5.5Ag1/5.5）46Al8 metallic glass was experimentally investigated. It exhibited linear and non-linear time-independent elastic deformation with a demarcative stress of approximately 500 MPa within the timescale in the present work, and repeated loading-unloading before yielding did not alter stress-strain relationship. The pure linear elastic strain limit is 0.6%, significantly lower than 2% as generally reported, but still much higher than 0.1% observed for typical crystalline alloys. Deviation from linear elastic behavior at stresses higher than 500 MPa is explained here as a macroscopic manifestation of local fluctuations in elastic strain, which becomes pronounced at stresses higher than the critical value. The occurrence of non-linear elasticity is possibly also related to the sinusoidal relationship between shear stress and atomic displacement.

关键词： Bulk metallic glass Tension test Elastic-plastic deformation

Tunability of the mechanical properties of(Fe_(50)Mn_(27)Ni_(10)Cr_(13))_(100-x)Mo_(x) high-entropy alloys via secondary phase control

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第14期73卷 210-217页

作者： Raymond Kwesi Nutor q.P.Cao X.D.Wang D.X.zhang J.z.jiang International Center for New-Structured Materials(ICNSM) Laboratory of New-Structured MaterialsState Key Laboratory of Silicon Materialsand School of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China State Key Laboratory of Modern Optical Instrumentation Zhejiang UniversityHangzhou 310027China

The single-phase face-centered cubic(fcc)-structured Fe_(50)Mn_(27)Ni_(10)Cr_(13) high entropy alloy(HEA)exhibits good ductility but low strength,which presents a *** Mo-alloying and thermomechanical treatments,we have designed the(Fe_(50)Mn_(27)Ni_(10)Cr_(13))_(100-x)Mo_(x)(x=0-6 at.%)alloy series with a wide range of mechanical *** careful control of secondary phases introduced in the cold-rolled and annealed(Fe_(50)Mn_(27)Ni_(10)Cr_(13))Mo_(2) sample resulted in an enhanced tensile strength from 250 MPa to 665 MPa,still having~25%*** investigations of this alloy revealed the presence of deformation twins,dislocation cells,and ordered bcc na no-pa rticles embedded in the ductile fcc matrix *** observed deformation structures are an indication of succes s ful cooperation between deformation twinning and precipitation strengthening in enhancing the tensile strength at maintained ductility compared to its cast *** work provides insight into the tunability of the mechanical properties of non-equiatomic HEAs via alloying and thermomechanical processing.

关键词： High-entropy alloys Mechanical property TEM

STUDY ON GRANULATION MECHANISMS OF γ+(Fe,Mn)3C EUTECTICS IN AUSTENITE STEEL COMPOSITES

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2003年第6期16卷 449-456页

作者： G.F.Liang z.M.Xu q.C.jiang J.G.Li SchoolofMaterialsScienceandTechnology ShanghaiJiaotongUniversityShanghai200030China SchoolofMaterialsScience JilinUniversityChangchun130025China

Results presented in this paper contribute to investigation of the granulation mechanisms of γ+(Fe,Mn)3C eutectics in the austenite matrix composites (abbreviated EAMC). The specimens corresponding to the nominal composition of eutectic with controlled RE(Ce)-Mg agent modifier additions have been unidirectional solidified with a constant growth rate of 2.18μm/s at a fixed temperature gradient of 800K/cm using vertical Bridgeman method. With the RE-Mg agent modifier, the transition of solid/liquid (S/L) interface from columnar to dendrite (CDT), refinement and developed branching of γ and (Fe,Mn)3C phases in the eutectics, and the transition of growth style from faceted-nonfaceted (F/NF) to nonfaceted-nonfaceted (NF/NF) for γ and (Fe,Mn)3C phases in the eutectic have been observed and investigated theoretically. Those can explain the granulation of γ+(Fe,Mn)3C eutectics in the as cast because the roundness increases with the developed lateral branching of primary austenite dendrites, refinement of eutectics, and NF/NF growth of γ and (Fe,Mn)3C phases in the eutectic.

关键词： composite RE-Mg agent granulation unidirectional solidifica-tion

Estimation of Temperature Rise in Stator Winding and Rotor Magnet of PMSM Based on EKF

在线全文

学校读者我要写书评

暂无评论

Estimation of Temperature Rise in Stator Winding and Rotor M...

HIGH TEMPERATURE FATIGUE BEHAVIOUR OF A DIRECTIONALLY SOLIDIFIED COBALT-BASE SUPERALLOY

2010 3rd International Conference on Computer and Electrical Engineering(ICCEE 2010)

作者： Xiaoliang jiang zhongying zhang Pindong Sun z.q. zhu School of Electrical and Automation Engineering Nanjing Normal University Department of Electronics and Electrical Engineering University of Sheffield

This paper proposed an estimation approach of temperature rise in stator winding and rotor magnet of a surfaced-mounted permanent magnet (PM) AC motor. By using the 3rd-order extended Kalman filter (EKF) algorithm in rotating reference frame, stator winding resistance and rotor PM flux-linkage can be estimated independently. After comparing the estimation results of resistance and flux-linkage to the rated values measured at 20 ℃respectively, the corresponding temperature rise in stator winding and rotor magnet can be calculated according to some certain rules. The proposed method was confirmed to be correct and effective by the simulation results from MATLAB/SIMULINK.

关键词： PMSM extended Kalman filter temperature rise estimation

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 1998年第2期11卷 111-115页

作者： W.H.jiang X.D.YAO H.R.GUAN z.q.HU Chinese Acad of Sciences Shenyang China

The high temperature high cycle fatigue behaviour of a directionally solidified Co-base superalloy was investigated. The alloy has saperior fatigue resistance at 900℃ and its fatigue strength is up to 295MPa. Its σ-Nf curve is characterized by three distinct zones. The stronger dependence of Nf on or in the high .and low stress zones results from multiple fatigue crock initiation sites produced by high stress and oxidation effect in a prolonged exposure, respectively.

关键词： directional solidification Co-base superalloy fatigue fracture

DEPENDENCE OF MICROSTRUCTURE SCALES OF EUTECTICS ON Ca-Si MODIFIER AMOUNT IN AUSTENITE STEEL COMPOSITES

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2004年第5期17卷 651-654页

作者： G.F.Liang z.M.Xu q.C.jiang J.G.Li SchoolofMaterialsScienceandTechnology ShanghaiJiaotongUniversityShanghai200030China SchoolofEnvironmentalScienceandEngineeringJiaotongUniversity Shanghai200030China SchoolofMaterialsScience JilinUniversityChangchun130025China

Results presented in this paper contribute to investigation of the effect of the added Ca-Si modifier amount ( ) on the microstructure scales of granular γ-(Fe,Mn)3C eutectics such as the volume fraction (f) and diameter (d) in the austenite steel matrix composites (EAMC). Directional solidification of EAMC has been carried out using vertical Bridgman method at 50.6μms-1 with a constant temperature gradient about 800Kcm-1. The higher constitutional supercooling ahead of solid-liquid interface attributing to the larger results in the enlargement of γ-(Fe,Mn)3C coupled-zone and the increment of the nucleation rate of eutectics. Therefore, f increases with increasing . The branches of the primary austenite dendrites develop more greatly as increases, which limits the growth of eutectics. As a result, d decreases with increasing .

关键词： austenite steel eutectic microstructure directional solidification