分别于真空和氮气气氛中,在1650,1750和1850℃对硅/碳化硅进行高温处理,通过光学显微镜、扫描电镜和X射线衍射仪研究了硅/碳化硅的组织变化.结果表明:氮气氛下,α子晶在界面能驱动下,通过基面以层状形式不断聚合长大,最终以完全"吞食"所包裹的β-SiC来完成相转变;在真空条件下,除了前一种方式外,还有一定的蒸发-凝聚烧结机制存在,两者同时作用使得比氮气条件下有较快的β-SiC转化速度.转化驱动力随温度的上升而提高.1 850℃氮气环境下处理的材料仍有少量β相存在,而真空1 750℃处理后就能得到单一α相的多孔材料.
参考文献
| [1] | 工業裂品技衍協会 .Ceramic Data Book 2000[J].工業と裂品,2000,128(82):155-160. |
| [2] | Chakrarti O P;Das P K;Mukerji J .Growth of SiC in reaction sintered SiC[J].Materials Chemistry and Physics,2001,67:199-202. |
| [3] | Shinoaki Samuel S;Noakes John E .Recrystallization and phase transformation in reaction-sintered SiC[J].Journal of the American Chemical Society,1978,61(5-6):237-242. |
| [4] | 杨于兴;漆王睿.X射线衍射分析[M].上海:上海交通大学出版社,1994 |
| [5] | A.L. Ortiz;F. Sanchez-Bajo;F.L. Cumbrera .X-ray powder diffraction analysis of a silicon carbide-based ceramic[J].Materials Letters,2001(2):137-145. |
| [6] | Zhou Hong;Singh Raj N .Kinetics model for the growth of silicon carbide by the reaction of silicon with carbon[J].Journal of the American Chemical Society,1995,78(09):2456-2462. |
| [7] | Li Jian-guo;Hausner Hans .Reaction wetting in the liquid-silicon/solid-carbon system[J].Journal of the American Chemical Society,1996,79(04):873-88o. |
| [8] | Ness J N;Page T F .Microstructural evolution in reactionbonded silicon carbide[J].Journal of Materials Science,1986,21:1377-1397. |
| [9] | Lim Chang-Bin;Iseki Takayoshi .Formation and transportation of intergranular and nodular fine-grained β-SiC in reactionsintered SiC[J].ADVANCED CERAMIC MATERIALS,1988,3(06):590-594. |
| [10] | Ogbuji L U;Mitchell T E;Heuer A H .The β→α transformation in polycrystalline SiC:Ⅲ,The thickening of α plates[J].Journal of the American Chemical Society,1981,64(02):91-99. |
| [11] | Heuer A H;Fryburg G A;Ogbuji L U et al.β→α transformation in polycrystalline SiC:Ⅰ,Microstructural aspects[J].Journal of the American Chemical Society,1978,61(9-10):406-412. |
| [12] | Lim C B;Iseki T .Strength-porosity-microstructure relationship in porous reaction-sintered SiC with free silicon removed[J].Journal of Materials Science,1990,31(08):4203-4210. |
| [13] | 饶东生.硅酸盐物理化学[M].北京:冶金工业出版社,1991 |
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