摘要
在不同催化剂催化条件下,使用化学液相沉积工艺制备了密度约为1.65 g/cm3的C/C复合材料,并对其微观组织、弯曲性能和弯曲试样的断口形貌,分别用偏光显微镜、万能材料试验机和扫描电子显微镜进行了表征。结果表明,化学液相沉积过程中,催化剂的引入对材料的组织结构与弯曲性能有显著的影响。未添加催化剂时,生成了光滑层组织的热解碳,材料的断裂形式为脆性断裂;使用Fe作为催化剂时,生成了光滑层和粗糙层混合组织的热解碳,材料的弯曲强度和弯曲模量有一定程度提高,断裂形式为假塑性断裂;使用Ni作为催化剂时,在炭纤维外围生成了粗糙层和各向同性层的双层热解碳,其断裂形式为假塑性断裂,但弯曲强度与未催化试样差别较小;使用Ni+Fe混合催化剂催化致密时,得到了粗糙层热解碳,其断裂形式为假塑性断裂,且弯曲强度和弯曲模量得到了明显提高。
C/C composite was prepared by chemical liquid vapor deposition （ CLVD ） at different catalytic conditions and its density was about 1.65g/cm3.The microstructure and flexural properties of the composites were characterized.The results show that the use of catalyst has significant impact on the structure and flexural properties of C/C composites during CLVD . When there is no catalyst added in the precursor,smooth laminar（ SL） pyrolytic carbon is formed and the fracture mode is brittle fracture. While Fe is used as catalyst, rough laminar （RL） and smooth laminar pyrolytic carbon structure is obtained.The flexural strength and flexurad modulas of the composites are improved and it shows pseudo plastic fracture.Rough laminar and isotropic （ISO） mixed structure is observed when Ni is added,and the composites show the pseudo plastic fracture behavior while the flexural strength is the same with the condition of nothing used as catalyst.The mixed Ni＋Fe catalyst added in the precursor induces rough laminar pyrolytic carbon and the composites exhibit pseudo plastic fracture behavior, and their flexural strength and flexural modulus are improved significantly.
出处
《固体火箭技术》
EI
CAS
CSCD
北大核心
2014年第4期574-577,共4页
Journal of Solid Rocket Technology
基金
国家自然科学基金创新群体项目(51221001)
国家自然科学基金面上项目(51222207)
教育部博士点基金(20126102110013)
