Dissertation > Excellent graduate degree dissertation topics show

Technique Research on the Preparation of MgB2 Film Via Molten Salts Electrochemical Method

Author: SunXiaGuang
Tutor: QiYang
School: Northeastern University
Course: Materials Physics and Chemistry
Keywords: Magnesium diboride Molten salt electrolysis Crystalline properties Superconductivity
CLC: TG662
Type: Master's thesis
Year: 2008
Downloads: 30
Quote: 0
Read: Download Dissertation

Abstract


MgB2 superconductor due to its similar intermetallic compared to the compound having a high transition temperature ( Tc = 39K ) and a high critical current density ( up to 105A/cm2 ) , compared with the oxide superconductor having easy processing , easy synthesis of advantages make it possible to get a wide range of applications . Joints the superconducting electrical applications pressing problem , conventional methods can not be a good deal . Molten salt electrochemical method can be prepared in any shape, size substrate film strip easily solve the problem of closed loop connectors molten salt electrochemical the best prepared MgB2 process experimental conditions has not been determined , the theory The research is still in its infancy. This thesis is trying to use molten salt electrochemical method MgB2 thin films prepared on different substrates . KCl-NaCl-MgCl2 ternary phase diagrams and fusibility diagram analysis , the calculation of the electrolysis voltage , to determine the range of the electrolytic parameters of the previous experiment . In the molten salt electrolysis prepared MgB2 film during the experiment , the first electrolysis equipment improvements, reducing the experimental difficulty as reactants ; Then, KCl, NaCl, MgCl2, MgB2O4 mixed system with DC power supply , using different temperatures in graphite , stainless steel, copper three cathode substrate , an electrochemically prepared MgB2 film; Finally, the use of X-ray diffraction (XRD) analysis sample phase , using a transmission electron microscope (TEM) and scanning electron microscope (SEM) to characterize the structure of the sample and shape appearance. Among them, the test Neo D/max-3A series X-ray diffractometer the standard debugging via the original method to achieve scientific analysis . Optimum temperature conditions in the copper substrate of the sample using standard four probe method to test the resistance with temperature variation curve ( RT curve) , the temperature-dependent variation of the magnetization curve (MT curves) were tested by SQUID . The results show that the MgB2 film having superconductivity can be prepared in a graphite, stainless steel , copper and three on the cathode substrate , and the optimum preparation of three on the substrate temperatures were 620 ° C , 598 ° C and 601 ° C . RT and MT results show that MgB2 film on a copper substrate superconducting transition occurs at about 50K . Phase purity and crystallinity of the film to be further improved , there is a weak connection between the grains , through the analysis of the molten salt system ( density , surface tension and viscosity ) , the molten salt system adjustment programs .

Related Dissertations

  1. Development of high sensitivity broadband channel receiver front-end system,TN858
  2. The Mass-radius Relation of Rotating Neutron Star under Color Superconductivity Phase and Latent Heat from Spin One Color Superconductivity Phase Transitions,P145.6
  3. Research on Superconductive Mechanism in Diamond,TQ164
  4. Renormalized Mean-field Theory for Interlayer Electron Tunneling Effects in Multilayer Cuprate Superconductors and Strongly Correlated Heterostructures,O511.4
  5. Effects of Carbon and Oxide on the Superconductivity of Doped MgB2,TM26
  6. Research on Detection Technology for Superconductor Pulse Power System,TN78
  7. The Design of the Critical Current Superconducting Switch and the Study of Its Breaking Characteristics,TM26
  8. Vibration Characters Research in HTS-PM Levitation System,TM26
  9. Study of Doping of Y1Ba2Cu3O7-δ Compounds,TM26
  10. Design and Simulation of HTS and Normal Conductor Coil Hybrid Suspension Vehicles,U266.4
  11. Effects on the Structure and Superconductivity of MgB2 Bulks by Ultrasonic Treatment and Glucose Doping,TM26
  12. Study on the Doping to Improve Grain Connectivity and Flux Pinning of MgB2 Superconductor,TM26
  13. Superconductivity and Magnectism in the Checkboard Models of Iron-Pnictides,O511
  14. Molten salt electrolysis preparation of gadolinium , yttrium and iron alloy Experimental Study,TF803
  15. Study on Fabrication of Superconducting MgB2 Thin Films,TB383
  16. The Preparation and Study on Magnesium-aluminum-strontium in Molten Salt Electrolysis Method,TF803.27
  17. Van Hove Singularity, Non-electron-phonon Interaction and the Superconductivity of HgBa2Can-1CunO2n+2+δ（n=1, 2, 3） System,O511
  18. On the Zero Set of the Solutions to Magnetic Schr(?)dinger Equations and the Partial Regularity of the Landau-de Gennes Energy Model for Liquid Crystals,O175.2
  19. T-EXAFS study of transition metal borides lattice dynamics and its isotope effect,O481.2
  20. Type superconductors in La_2CuO_4 charge ordering and its ultrasonic attenuation characteristics,O511
  21. New series MgB_2 superconductors superconductivity and microstructure,O511

CLC: > Industrial Technology > Metallurgy and Metal Craft > Metal cutting and machine tools > Special machine tools and processing > Electrochemical machining machine tools and processing
© 2012 www.DissertationTopic.Net  Mobile