摘要
在氮气氛中于1650-1850℃的温度范围内对硅/碳化硅材料进行高温处理。通过光学显微镜、扫描电镜和X射线衍射方法,研究反应烧结碳化硅材料的中各相组织及成分随热处理温度的变化规律。结果表明,晶间粒状次生β相SiC首先以溶解-析出形式发生再结晶,而后沉积在α相碳化硅上,通过-αSiC相基面的不断长大,完成β相向α相的转变。从能量的观点在理论上探讨了反应烧结碳化硅中β→α的相转变机理。
Si/SiC composites were treated under nitrogen atmosphere at a temperature range of 1650-1850°C.The evolution of microstructure and phases of Si/SiC composites were investigated by means of optical microscopy, scan electrical microscopy and X-ray diffraction. The results indicate that the newly formed intergranular nodular β-SiC is first recrystallized by solution-precipitation and then deposits epitaxially on the original α-SiC particles. The β-SiC is transformed into α-SiC phase by the growing of a-SiC base plane. The mechanism of β &rarr α transformation in Si/SiC composites is discussed on the basis of interface energies.
出处
《材料热处理学报》
EI
CAS
CSCD
北大核心
2006年第2期11-14,共4页
Transactions of Materials and Heat Treatment
基金
国家"十五"863科技攻关资助项目(2001AA333010)
关键词
硅/碳化硅
热处理
显微组织
相组分
Composite materials
Deposition
Heat treatment
Nitrogen
Protective atmospheres
Recrystallization (metallurgy)
Silicon
Silicon carbide
