摘要
研究了碳的添加量为6wt%条件下,添加碳源的种类及添加比例对制备的无压固相烧结碳化硅陶瓷的微观结构和性能的影响。结果表明:采用纯无机碳源(碳黑),制备的碳化硅陶瓷具有较为细小的碳化硅晶粒结构,但致密度较低;添加有机碳源(酚醛树脂)时,随着其裂解碳添加量的增加,碳化硅的晶粒逐步长大,碳在材料中的分布更加均匀,材料的致密度提高,力学性能增强。当有机碳源裂解碳添加量达3wt%时,材料的致密度最高,并具有最大的弹性模量468 GPa,断裂韧性达4.65 MPa·m1/2。当有机碳源裂解碳添加量大于3wt%时,碳化硅晶粒发生局部异常长大现象,材料的弯曲强度与断裂韧性进一步增加。同时,对材料的热扩散系数随碳源添加种类和比例变化的规律也进行了分析与讨论。
With 6wt% total carbon additive amount, the microstructure and properties of pressureless solid-state sin- tered SiC（SSiC） were studied with different carbon sources and carbon source adding ratio. It is found that SSiC ce- ramics with inorganic carbon （carbon black） as carbon source have finer SiC grains and lower density. As the carbon additive amount derived from organic carbon source （phenolic resin） increases, the grain size of SiC grains in SSiC ceramics increases, the distribution of carbon phase in the ceramics is more homogeneous, the density and the me- chanical properties of SSiC ceramics increase. When the carbon additive amount derived from organic carbon source is 3.0wt%, the ceramics with highest density have the largest elastic modulus, which is up to 486 GPa, the fracture toughness of it is 4.65 MPa .m1/2. When the carbon additive amount derived from organic carbon source is over 3.0wt%, the abnormal grain growth of SiC grains appears in the ceramics, the fracture strength and toughness further increase. At the same time, the thermal diffusion coefficient of SSiC ceramics with different carbon sources and adding ratio is also discussed.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2013年第9期1009-1013,共5页
Journal of Inorganic Materials
