碳化硅材料中游离硅及游离碳对性能的影响

The influence of free silicon and free carbon to Melt-infiltrated Silicon Carbide

研究了全碳粉反应渗硅碳化硅（PCRBSC）材料的结构与力学性能的关系,分析了渗硅碳化硅材料中游离硅（fsi）、游离碳（fc）含量对抗折强度的影响。结果表明:渗硅碳化硅材料中随游离硅（fsi）含量的增加,其抗折强度下降,并且二者呈直线关系,符合线性复合规刚。另一方面,游离碳（fc）含量较高的渗硅碳化硅材料,尽管游离硅（fsi）含量低,但其抗折强度低于等量或较多游离硅（fsi）含量的渗硅碳化硅材料的抗折强度。

The relation of structure and mechanical properties of pure carbon melt-infiltrated silicon carbide (PCRBSC)is investigated. The influence of the free silicon content and free carbon content on flexural strength is analysed. Experimental result shows that the flexural strength of melt-infiltrated silicon carbide decreases linearly with volume percent of free silicon content which obeys linear mixture rule. At higher free carbon content, the flexural strength of melt-infiltrated silicon carbide is lower than that of melt-infiltrated silicon carbide with equal or more free silicon even though there is no free silicon or rare free silicon content.