Dissertation > Excellent graduate degree dissertation topics show

Synthesis of Al4SiC4 from Al2O3, Al2Si2O5（OH）4 and C as Raw Materials

Author: BaiChunLi
Tutor: LiXiuHua；ZhaoJianLi
School: Tianjin University
Course: Materials Engineering
Keywords: Al4SiC4 synthesis carbothermic reduction kaolinite
CLC: TB383.1
Type: Master's thesis
Year: 2008
Downloads: 31
Quote: 0
Read: Download Dissertation

Abstract


Al4SiC4 probably can be used as nonoxide raw material for structure ceramics and refractories with excellent properties.From the reports so far, Al4SiC4 was synthesized by using starting materials of metal+carbon, metal+oxide+carbon or carbides.The present research investigated factors influencing the synthesis of Al4SiC4 by using starting materials of Al2O3, Al2Si2O5（OH）4 and C.Powder mixture or compact mixture had no obvious difference on Al4SiC4 formation. Al4SiC4 was observed from 1500℃and the formation quantity was increased with raised temperature. Al4O4C was detected from 1550℃and was decreased after increased with raised temperature. There was not mullite phase in the samples heated at 1450℃and higher temperatures and all SiO2 had been reducted into SiC at 1450℃. For the mixtures with C:Al2O3:Al2Si2O5（OH）4=24:3:1 and 16:3:1, the reactions were sufficient when heated at 1700℃for 5h and 7h. The residual SiC in the formation product was gradually decreased by reducing the ratio of Al2Si2O5（OH）4 in the mixtures. Pure Al4SiC4 phase was formed when heating the mixture with C:Al2O3:Al2Si2O5（OH）4=16:3.3:0.7. The residual Al4C3 was observed when further reducing the ratio of Al2Si2O5（OH）4 in the mixtures. The pure Al4SiC4 phase had grain sizes with about 4～7μm length, about 2～4μm width and about 1～2μm thickness. Grain sizes of Al2O3 or Al2Si2O5（OH）4 had remarkable influence on composition of the product. When the grain size of Al2O3 or Al2Si2O5（OH）4 was increased, there was residual SiC besides Al4SiC4 in the formation products. Graphite or carbon black as C material had no obvious influence on composition of the product. Combining the test results and thermodynamics calculations, it was known that SiC was formed firstly, Al4O4C secondly and Al4SiC4 lastly when the mixture was heated. Al（g）、Al2O（g）、SiO（g） and CO（g） were primary volatility gases in the reactions.

Related Dissertations

  1. Studies on the Synthesis and Technology of Dipentaerythritol and Its Derivative,TQ223.164
  2. Synthesis and Characterization on Semi-Aromatic Polyamides Containing Benzoxazole Units,O633.5
  3. Video Coding Research Based on Texture Characteristics,TP391.41
  4. Poetic alienation : graphics,J506
  5. Urothermal Synthesis, Structure and Characterization of Functional Coordination Polymers,O631.3
  6. Atovaquone analogues Design, Synthesis and antitumor activity of,R914
  7. Synthesis and Seperation of 1,1’-binaphthol,O625.3
  8. Flexible,rigid,Synthesis and characterization of mixed ligand complexes,O621.1
  9. Study on the Mechanism of Night Temperature to Grain Filling of Inferior in Rice,S511
  10. Gold-catalyzed Addition Reaction of Sulfonates and Alkynes and Study of Synthesis and Bioactivity of (E)-3-phenyl-substituted Acrylic Acids,R914
  11. Curing Mechanism and Properties of Fluorenyl Epoxy Resin,TQ323.5
  12. Study on Antioxidant Activities and Lipase-catalyzed Transesterification of Lard to Produce L-ascorbyl Fatty Acid Esters,TS202.3
  13. Syntheses of Novelbenzopyran Compounds Containing Fluorine and Induced Resistance to TMV,S435.72
  14. Research on the Physiology Mechanism of Grain Filling of inferior Grain during Day and Night Chemical Regulations,S511
  15. Expression of β-Catenin in Pig’s Ovary and the Effect of β-Catenin on Porcine Granulosa Cells Apotosis and Steroidogenesis Related Enzyme,S828
  16. The Problems and Solutions of University’s Ideological and Political Education under Network Environment,G641
  17. Synthesis and Reactions of Organo Lithium, Potassium, Magnesium Compounds,O621.13
  18. Synthesis and Structures of Metal (Mn, Zn and Sn) Complexes Incorporating with the Sily-linded Bis (Amidinate) Ligands,O621.2
  19. Synthesis and Fungicidal Activity of 2-Acyloxycycloalkylsulfonamides,S482.2
  20. The Study on the Preparation of McAb to Anti-Melemine and Establishment of Ic-ELISA for Detetion of Melamine,S859.84
  21. The Oxidation Mechanism and Stability Improved of Conjugated Polyunsaturated Fatty Acids,O621.25

CLC: > Industrial Technology > General industrial technology > Materials science and engineering > Special structural materials
© 2012 www.DissertationTopic.Net  Mobile