预制体尺度对C/C复合材料CVI增密过程影响的模拟研究  

Simulation study on the influence of the scale of preform to the densification in CVI process of C/C composite

作　　者：徐鹏[1] 廖敦明[1] 李晋[2] 周建新[1] 孙飞[1] 董长春[1] 

机构地区：[1]华中科技大学材料科学与工程学院,湖北武汉430074 [2]中国航天科技集团公司四院四十三所,陕西西安710025

出　　处：《功能材料》2013年第21期3076-3080,共5页Journal of Functional Materials

基　　金：中央高校基本科研业务费资助项目(2012TS010);教育部新世纪优秀人才支持计划资助项目(NCET-09-0396);湖北省自然科学基金创新群体资助项目(2010CDA067)

摘　　要：对不同直径圆柱预制体的CVI增密过程进行数值模拟研究,分析预制体尺度对增密过程及密度分布的影响。针对高90mm,直径分别为60、120、180mm的预制体,分别模拟CVI过程中预制体的孔隙率、密度以及孔隙平均尺寸分布和变化特征。结果显示,小直径预制体经过一段时间的沉积后密度分布较为均匀,且平均密度值很高;预制体直径较大时,沉积易发生在表面区域,导致表面区域密度较高,中心区域密度值较低,影响进一步的增密过程。CVI processes of different diameter of preforms were studied in this research to analyze the influence of the scale of perform to the densification in CVI. Preforms of the equivalent height of 90mm and each diame ter was 60, 120 and 180mm was used to simulate the porosity and density field in 4 periods. Results showed that it was easy to get uniform and high score of density in small diameter preform, when crust occurred on the surface of larger diameter preform, additionally, in larger size preform density in surface area was higher and negative density gradient formed from the center to the boundary of the final product.

关 键 词：预制体尺度 CVI 模拟 周期 密度梯度 

分 类 号：TB332[一般工业技术—材料科学与工程]