Dissertation > Excellent graduate degree dissertation topics show

Research on Microstructure and Magnetic Property of Amorphous Fe-Si

Author: WangWeiGuang
Tutor: SunYue
School: Harbin Institute of Technology
Course: Materials Science
Keywords: Amorphous Crystallization heat treatment FeSi alloy Soft magnetic
CLC: TG132.271
Type: Master's thesis
Year: 2009
Downloads: 48
Quote: 0
Read: Download Dissertation

Abstract


Fe-based amorphous soft magnetic alloy having excellent soft magnetic properties, such as high permeability, resistivity, and low magnetic loss, the coercive force is small, small magnetostriction. The thermodynamic metastable structure since the amorphous belongs, however, in certain conditions, the crystallization occurs, thereby affecting the soft magnetic properties of the material. The corresponding solutions is controlled crystallization process, to get the organization to improve the stability of the nanocrystals, while the soft magnetic properties are not obvious deterioration. The amorphous foil existing EBPVD equipment improvements. A substrate cooling system in order to avoid the deposition of the process occurred amorphous - crystallization phase transition, the process of the preparation of amorphous FeSi foil final. Prepared state amorphous alloy microstructure and electromagnetic properties subsequent crystallization heat treatment, the alloy microstructure and electromagnetic properties of the study the crystallization process parameters and crystallization treatment; then preparation state amorphous FeSi alloy . The results show that the alloys were prepared were amorphous structure, mainly containing Fe and Si, two elements, and the silicon content is very low, about 0.197%. The Inoue ingredients qualification recognized based on the field of bulk amorphous, impossible to get this the simple Bipropellant amorphous. The reason for breaking this component defined conditions, that using the process with a high cooling rate. XRF, XRD, AFM, PPMS VSM variety of testing methods, the composition of the alloy in the the preparation state amorphous alloy crystallization process, organizational structure, morphology and electromagnetic properties characterize the resistance of the alloy is ρ = 5.68 × 10-4? mm, its value is greater than the resistivity of the silicon steel sheets (4.4 × 10-4? mm). Preparation of alloys with high initial permeability (13,000) and high saturation magnetic flux density (2.1T), this saturation magnetic flux density is close to electrical pure iron. The crystallization process parameters significantly affect the alloy microstructure and electromagnetic properties. With the elevated temperature of the crystallization heat treatment, the alloy amorphous component reduced, increase in the crystalline component originally present in the alloy particles begin to differentiate, and the formation of many small particles of nanometer sizes. Crystallization heat treatment temperature increases, crystal phase increases monotonically decreases the resistivity of the alloy, but the magnetic no significant change. Applying an external magnetic field, when the crystallization heat treatment, and found that the microstructure of the alloy structure and the resistivity variation was no significant difference, but can lead to increase in the degree of the anisotropy of magnetic energy, along the direction of the magnetic field on the soft magnetic properties superior to the perpendicular to the field direction.

Related Dissertations

  1. Investigations of Structure and Glass Forming Abilty of Amorphous Alloys,TG139.8
  2. Degradation of Amorphous Silicon Thin Film Transistors under Gate and Drain Voltage Bias Stress,TN321.5
  3. Medical magnesium alloy surface laser cladding Zr 60 Ti 6 Cu 19 Fe 5 Al 10 amorphous coating,TG174.44
  4. Research on Amorphous and Nanocrystalline Soft Magnetic Dynamic Measurement System Based on Virtual Instrument,TM271.2
  5. Research and Development of the Inductance Measuring Meters of Amorphous and Nanocrystalline Soft Magnetic Materials,TM271.2
  6. Mechanical Properties of Bulk Amorphous Alloys and Bulk Amorphous Alloy Matrix Composites,TG139.8
  7. Isolation and Characterization of Functional Microorganism in Microbial Electrolysis Cell (MEC),TQ116.2
  8. Study on Nitrogen Doped Tetrahedral Amorphous Carbon Films Prepared by FCVA and Their Applications,TM914.4
  9. Process and Microstructure Studies of Nitridation Combined with Trivalent Chromium Electroplating on Pure Iron,TG156.82
  10. Dynamics study of plastic deformation induced crystallization of amorphous alloy,TG139.8
  11. Effects of Additional Element on the Glass Forming Ability and Mechanical Properties of Bulk Zr-based Amorphous Alloys,TG139.8
  12. Fe-based amorphous alloy crystallization kinetics of,TG139.8
  13. The Effect of Semi-solid Processing of the Zr-based Amorphous Alloy on Organization Structure and Mechanical Properties,TG139.8
  14. Study on Diffusion Bonding of Zr-based Bulk Metallic Glasses,TG139.8
  15. The Research on the Process and Mechanism of the Al-Based Amorphous Alloys during Diffusion Bonding,TG139.8
  16. The Research on Casting Properties of Zr-based Amorphous Alloy,TG139.8
  17. H Non-crystalline Granular Corn Starch by Semidry Process:preparation & Mechanisms,TS231
  18. Cobalt-based soft magnetic properties of glass wrapped wire Optimization,O482.5
  19. Research on an Axialradial-Radial Flux Compound-Structure Permanet-Magnet Synchronous Machine Used for Hybrid Electric Vehicle,TM351
  20. Low-dimensional amorphous ferroelectric materials Preparation and luminescence characteristics,TB34

CLC: > Industrial Technology > Metallurgy and Metal Craft > Metallurgy and Heat Treatment > The alloy learn with a variety of properties of alloys > Special physical properties of alloys > Special electromagnetic properties of alloy > Special magnetic properties of the alloy > Soft magnetic alloy
© 2012 www.DissertationTopic.Net  Mobile