高韧性炭/炭复合材料的制备及研究
Preparation and Research of High-Toughness C/C Composites
张泽 1张明瑜 1方婉娴 1徐平 1曾晨 1高莹 2苏哲安 1黄启忠1
作者信息
- 1. 中南大学轻质高强结构材料国家级重点实验室,长沙 410083
- 2. 北京中材人工晶体研究院有限公司,北京 100018
- 折叠
摘要
C/C复合材料是一种高性能新型复合材料,但是脆性大、韧性差的缺点限制了其广泛应用.因此,本研究利用化学气相渗透(CVI)法,设计并制备了三种C/C复合材料,基体炭分别为粗糙层、光滑层以及粗糙层/各向同性层带状结构热解炭,研究了 C/C复合材料的微观结构、沉积机理、断裂行为和增韧机制.结果表明,三种C/C复合材料的抗弯强度分别为189.1、191.5、233.5 MPa.粗糙层和带状结构炭基体的C/C复合材料为假塑性断裂,而光滑层炭基体的C/C复合材料则是明显的脆性断裂.与粗糙层炭基体的C/C复合材料相比,带状结构炭基体的C/C复合材料通过不同结构热解炭之间的界面滑动,使得应变量增加了约70％,韧性得到了提升.因此,通过控制CVI工艺参数,实现带状结构热解炭制备,可以有效优化C/C复合材料的韧性.
Abstract
C/C composites are a new type of high-performance composites,but their shortcomings of high brittleness and poor toughness limit their wide application.Therefore,in this study,three kinds of C/C composites were designed and prepared using the chemical vapor infiltration(CVI)method with matrix carbon:rough layer,smooth layer,and rough layer/isotropic layer band-structured pyrolytic carbon(PyC),respectively.And the microstructures,fracture behaviors,and toughening mechanisms of C/C composites were investigated.The results indicate that the flexural strength of the three C/C composites is 189.1,191.5,and 233.5 MPa,respectively.The C/C composites with rough layer and band-structured carbon matrix are pseudoplastic fractures.In contrast,the C/C composites with smooth layer carbon matrix are brittle fractures.Compared to the C/C composites with rough layer carbon matrix,the C/C composites with band-structured carbon matrix show a significant increase in toughness through interfacial sliding between the different structured pyrolytic carbon,which increases strain amount by about 70％.Therefore,the toughness of C/C composites can be effectively optimized by controlling the parameters of the CVI process to achieve band-structured pyrolytic carbon preparation.
关键词
C/C复合材料/化学气相渗透/层间滑动/断裂模式/带状结构/高韧性Key words
C/C composite/chemical vapor infiltration/interlayer sliding/fracture mode/band-structure/high-toughness引用本文复制引用
基金项目
国家自然科学基金(U19A2088)
长沙市重大项目(kh2103012)
出版年
2024
国家科技期刊平台
NSTL
万方数据