Dissertation > Excellent graduate degree dissertation topics show

Preparation of Al-based Ceramic Composite Coatings by the Method of Mechanical Alloying

Author: GuoYan
Tutor: ShenYiFu
School: Nanjing University of Aeronautics and Astronautics
Course: Materials Processing Engineering
Keywords: mechanical alloying Al-based ceramic composite coating milling parameters frictionwearness high-temperature oxidation resistance
CLC: TG174.453
Type: Master's thesis
Year: 2012
Downloads: 41
Quote: 0
Read: Download Dissertation

Abstract


During the process of the mechanical alloying, due to the repeated collisions the powderundergoes cold welding and fragment, a collection of powders tend to adhere to the surface of ballsand the inner wall of chamber, for which a coating layer of certain thickness forms. Based on the“pollution”, Al-ZrO2-Y2O3、Al-Al2O3and Al-Al2O3-ZrO2-Y2O3powders were used to prepare theAl-based ceramic composite coatings using five different milling-parameter in this paper.The Al-ZrO2-Y2O3coating was firstly deposited on the surface of SUS304. The results showedthat the micro-hardness of the surface, the friction-wearness and the the high-temperature oxidationresistance of the coating were well proved.The Al-Al2O3composite coating was obtained by MA with the same milling parameters, it wasfound that its microstructure was fully improved, that the thichness of coatings turned larger andcracks became less. We also found that the coatings of largest thickness up to0.6mm were obtainedwhen the rotate speed was400r/min after8hours’ milling, of which the micro-hardness was thelargest and the friction coefficient was the smallest, also the coatings’ high-temperature oxidationresistance got better contrasting with Al-ZrO2-Y2O3coating syetem.The Al-Al2O3-ZrO2-Y2O3composite coating was obtained by MA under the same millingcondition. Though the thickness of Al-Al2O3-ZrO2-Y2O3composite coating was smaller than theAl-Al2O3coating, author found that the consistence and the homogenization were well enhanced. Theproperties that micro-hardness, friction wearness and the high-temperature oxidation resistance gotthe best when setting a bowl rotation speed of400r/min and a milling time of8h.Based all of the results, the author also studied the fabrication principle of Al-based ceramiccomposite coatings by mechanical alloying and the mechanism of the high-temperature oxidationresistance that Al has influence on the Al-based ceramic composite coatings.

Related Dissertations

  1. Studies of Plasma Spray Metal-Ceramic Compounds Coatings on Q245r Steels,TG174.44
  2. Manufacture and Property Research on FeAl Based Porous Material,TF124.5
  3. Preparation and Thermoelectric Properties of Ag(Pb1-ySny )m SbTe2+m-based Materials,TB34
  4. Microstructure and Properties of 9Cr-ODS RAFM Prepared by PM,TG142.1
  5. Study on the Preparation and Thermostability for Mechanical Properties Microstructure of Low Density MA/ ODS Nickel-Based Superalloy,TG132.32
  6. Study on Hydrogen Storage Properties and Preparation of Mg-Ti-Based Alloys,TG139.7
  7. Research on Microstructure and Properties of Ti(C, N)-based Cermets Coated by Multivariant Nitrides,TG174.4
  8. Synthesis of Ag / Al 2 O 3 powder composites research,TB383.3
  9. Titanium sponge reactor temperature oxidation resistant coating Preparation and Mechanism,TG174.442
  10. Research on High-temperature Oxidation Property of Calorized Coatings on GH907 Superalloys,TG174.44
  11. Preparation and Properties of Functional Composite Coatings Embedded ZrO2 Ceramic Particles,TG174.4
  12. WCu electrical contact products injection molding process and performance studies,TF124.3
  13. Phase Transformation During the Sintering of the ODS Ferritic Heat-Resistant Steel,TF124.5
  14. Study on High Silicon Coating by Dc-Plasma Jet Surface Metallurgy,TG174.4
  15. Study on Preparation of high-performance -doped lanthanum lead zirconate titanate piezoelectric ceramics,TQ174.6
  16. Study on Microstructure Properties and Deformation Behavior at High Temperature of Al-Pb Alloy,TF124.5
  17. TiAl Alloys SPS sintering of Microstructure and High Temperature Oxidation,TF124.5
  18. Laser Direct Metal Deposition (DMD) of Ni-Base Superalloy and Its High Temperature Oxidation Resistance,TF124.39
  19. Preparation of Nonstoichiometric CrN_x by Ma and Its Sintering Characteristric,TF124.5
  20. The Synthesis of B4C Composite and the Research of Its Corrosion Behavior in Sea Water,TG174.3
  21. The Study of the Influence of Cr on the Cyclic Oxidation Life of Hot-dipped Coating,TG174.44

CLC: > Industrial Technology > Metallurgy and Metal Craft > Metallurgy and Heat Treatment > Metal corrosion protection,metal surface treatment > Corrosion control and protection > Metal surface protection technology > Inorganic complex layer of protection > Ceramic stratified
© 2012 www.DissertationTopic.Net  Mobile