| The thesis studied AlN inorganic high thermoconductivity material which is suitable to compound with corundum ceramic and enhances its heat conduction performance and the effects of compound optimization with corundum ceramic as well as the prepared technology on thermoconductivity performances, and obtained new AlN/Al2O3 compound material with high thermconductivity. The thermoconductivity of AlN/Al2O3 composite sintered at 1560℃for 60min under oxidizing atmosphere was enhanced to be 120% compared with 96 alumina ceramic, and mechanics performance also had the distinct enhancement.The measured results by a serial of methods, such as XRD, SEM indicated that the main reason for improved thermoconductivity of corundum ceramic is the host-crystal grain size growth due to appropriate AlN content addition. The CaF2, MgF2 fluoride as sintered reagent can be possible to promote the host-crystal grain growth and the crystal form integrity, which is good to enhance heat conduction performance. But grain size non-uniformity and partial crystal grain coarsening caused mechanics performance drop. The technology parameters, such as ball grinding medium, fire ambience, and dwelling time and so on had the obvious effects on thermoconductivity of compound material. In all, the experimental results showed that the main factors affected the thermoconductivity are crystal phase type and corresponding quantity, crystal grain size and the porosity in compound material. All which affect thermal conductivity of the compound material is integrated action of microstructure.The mathematical statistic analysis of experimental results obtained when the content of addition of AlN is less than 10%, regarded the effects of AlN additive content (XAlN), the crystal grain size in microstructure (D) and the true porosity (Pt) on thermoconductiveity of compound materials, the single factor linear return empirical equation respectively is:λ′=106.7+21XAlNλ′=-44.6 +40Dλ′=334.4-3479Pt... |
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