Dissertation > Excellent graduate degree dissertation topics show

Phase Selection in Undercooled Melts of Cu-Ge Peritectic Alloys

Author: LuoGang
Tutor: GaoJianRong
School: Northeastern University
Course: Materials Science
Keywords: Copper alloy Peritectic alloy Solidification Supercooled Phase selection
CLC: TG111.4
Type: Master's thesis
Year: 2008
Downloads: 26
Quote: 0
Read: Download Dissertation

Abstract


The undercooled peritectic alloy phase selection has a very important significance , because it not only contribute to the awareness of non-equilibrium solidification process , and there is a very important value of industrial applications . Undercooled state , many important materials are related to the phase selection , such as permalloy , stainless steel , rare earth permanent magnetic materials and rare earth oxide high-temperature superconducting materials . However , the law and mechanism of the peritectic alloy phase selected there is no clear and unified understanding , therefore be studied in depth . In this paper, copper germanium peritectic alloy (Cu-14.8% Ge) and over peritectic alloy (Cu-18% Ge) model alloy by electromagnetic levitation technology undercooled rapid solidification and phase selection studies and the glass substrate hanging quenching , the copper substrate hanging quench the drop tube experimental results were compared to examine the undercooling and cooling rate on regular undercooled melt phase selection . Electromagnetic levitation experiment ' peritectic component alloy obtained 157K-244K undercooling over peritectic composition alloy obtained 124K-241K undercooling , the primary phase are α -Cu . Peritectic composition alloy the glass substrate hanging quenching experiments 32K-174K undercooling , the primary phase is α -Cu ; over peritectic composition alloy to obtain 179K ~ 294K undercooling , when undercooling exceeds 280K after the primary phase for the peritectic phase ζ- Cu5Ge . The copper base overhang quenching experiments , the two components of the alloy of peritectic phase the ζ-Cu5Ge can be a primary phase in the form of precipitation . Drop tube experiments , the ingredients of peritectic alloys and alloys of the most over- peritectic composition in the newborn phase, α-Cu, only in a few too peritectic composition alloy peritectic phase of ζ-Cu5Ge to the primary phase in the form of precipitation. The above results show that , the peritectic alloy in the melt of the copper- germanium peritectic phase precipitated form of the primary phase is very difficult . However , as long as the undercooling is large enough (gt; 280K), even low cooling rate peritectic phase ξ-Cu5Ge can also become the primary phase . The undercooled peritectic alloy of copper germanium melt phase selection , undercooling is the decisive factor , the cooling rate is induced factors .

Related Dissertations

  1. Coupled Calculation of the Solidification Paths of Ternary Eutectic Alloys Based on Thermo-Calc,TG111.4
  2. Numerical Simulation in Directional Solidification of Steel Ingot and the Study of Insulation Effect by Hollow Sidewall,TG111.4
  3. Phase-field Simulation of Forced Flow Effect on Solidification Microstructure,TG111.4
  4. Research on the Pilot Protection and the Fault Phase Selection for Double Circuit Lines on the Same Tower,TM773
  5. Numerical Simulation of Granulation and Waste Heat Recovery Process for Blast Furnace Slag,X757
  6. Research of Microalloying Nb and Ti in Ultra-purity 430 Ferritic Stainless Steel,TG142.71
  7. Effect of Cooling Rate on Microstructure Evolution of Mg-Zn-Y/IQC in Situ Composites,TB331
  8. Modifying Effect of Nano-Inoculant on ZL109 Aluminum Matrix Composites,TB331
  9. Numerical Simulation on Solidification and Heat-transfer of Hazelett Continuous Casting of Aluminum Alloy Slab,TF777
  10. Numerical Simulation and Experimental Investigation on Solidification of Zn-Al Alloy,TG244.3
  11. The System of Phase Selection Based on Signal Processing,TN911.7
  12. Microstructure Evolution of Directionally Solidifiied Ti-53at%Al Peritectic Alloy,TG111.4
  13. Study on Separation of Metal Elements in Municipal Solid Waste Incineration Fly Ash,X705
  14. Experimental Study on the Treatment of Cd, Pb and Cr-polluted Soil with Lime and Fly Ash,X53
  15. Simulation of Huge Rectangular Ingot by Different Intensive Cooling,TG244.3
  16. Investigation on Solidification Cracking Susceptibility of 690 Nickel-based Welding Strip Surfacing Metal,TG457
  17. Steel Casting Technology Analysis and Optimization Based on Numerical Simulation,TG260
  18. Study on the Plastic Deformation Behavior of Mg65Cu25Y10-xNdx Bulk Amorphous Alloy,TG139.8
  19. Research on Influencing Factor of Thermal Fatigue Performance in Unidirectional Solidification of Al-Cu Alloy,TG111.4
  20. Study of Laboratory Simulation on Billet and Bloom Continuous Casting with Linear Electromagnetic Stirring,TF777.2
  21. Research on Aluminum Matrix Composites Reinforced with Intermetallics,TB331

CLC: > Industrial Technology > Metallurgy and Metal Craft > Metallurgy and Heat Treatment > Metallurgy ( Physical Metallurgy ) > Physics of metals > The liquid structure of the metal and solidification theory
© 2012 www.DissertationTopic.Net  Mobile