树脂基多孔碳孔结构对C_(f)/SiC复合材料连接性能的影响  

Effect of Pore Structure of Organic Resin-based Porous Carbon on Joining Properties of C_(f)/SiC Composites

作　　者：吴西士 朱云洲[2] 黄庆[1] 黄政仁 WU Xishi;ZHU Yunzhou;HUANG Qing;HUANG Zhengren(Ningbo Institute of Materials Technology&Engineering,Chinese Academy of Sciences,Ningbo 315201,China;Shanghai Institute of Ceramics,Chinese Academy of Sciences,Shanghai 201899,China)

机构地区：[1]中国科学院宁波材料技术与工程研究所,宁波315201 [2]中国科学院上海硅酸盐研究所,上海201899

出　　处：《无机材料学报》2022年第12期1275-1280,共6页Journal of Inorganic Materials

基　　金：国家重点研发计划(2021YFB3701500);国家自然科学基金青年项目(52002379);浙江省博士后科研项目择优资助。

摘　　要：连接技术是实现大尺寸以及复杂构型C_(f)/SiC复合材料制备及工程化应用的关键技术。本工作使用酚醛树脂作为碳源,通过反应连接法实现了C_(f)/SiC复合材料的稳定连接,研究了多孔碳坯的体积密度和孔径对接头连接性能和微观结构的影响,讨论了惰性填料含量对接头连接性能和显微组织的影响。研究表明:树脂基多孔碳素坯的体积密度和孔径分别选定在0.71~0.90 g·cm^(-3)和200~600 nm比较合适,随着多孔碳素坯孔径增加,游离硅尺寸逐渐增大;当孔径为190nm时,连接件强度最大为(125±12)MPa。添加SiC惰性填料可以明显减小多孔碳素坯的体积收缩,当SiC惰性填料质量分数为50%时,连接件强度最高达到(216±44) MPa,基本与基体材料强度相当。总体而言,本研究为实现C_(f)/SiC复合材料稳定连接提供了理论指导,对实现复杂形状或大型C_(f)/SiC复合材料的制备和工程应用具有重要意义。Joining technology has become an important part of the preparation and engineering application of large or complex-shaped C_(f)/SiC composites. In this study, the stable joining of C_(f)/SiC composites was achieved via the Si-C reaction joining method by using the phenolic resin as the carbon precursor. Effects of the bulk density and pore size of porous carbon blanks on the joining properties and microstructure of the joints were investigated. Effect of the content of inert fillers on the joining properties and microstructure of joint were discussed. Bulk density and pore size of the resin-based porous carbon blank are suitable to be set in the range of 0.71-0.90 g·cm^(-3)and 200-600 nm,respectively. The size of free silicon increases gradually with the increase of the pore size. The flexural strength of the joined specimens can reach(125±12) MPa at pore size of 190 nm. Addition of SiC inert filler is obviously beneficial to reduce the volume shrinkage of the porous carbon blank. Flexural strength of the joined specimens reached the highest value, i.e.,(216±44) MPa at the inert filler content of 50%. Overall, this study provides theoretical guidance for the stable joining of C_(f)/SiC composites, which has significance for realizing the preparation and engineering application of complex-shaped or large C_(f)/SiC composites.

关 键 词：多孔碳 反应连接 C_(f)/SiC复合材料 力学性能 微观结构 

分 类 号：TQ174[化学工程—陶瓷工业] TB332[化学工程—硅酸盐工业]