软硬混编预制体增强沥青基4D-C/C材料弯曲行为  

Flexural behavior of carbon fiber and carbon rod coweaved preform reinforced pitch-based 4D-C/C composites

作　　者：吴小军[1] 刘博[1] 韩明[2] 嵇阿琳[1] 崔红[1] 

机构地区：[1]西安航天复合材料研究所,陕西西安710025 [2]中国人民解放军驻210所军事代表室,陕西西安710065

出　　处：《炭素技术》2014年第5期34-38,共5页Carbon Techniques

摘　　要：以z向穿插炭棒、x-y向铺层纤维束法编织的软硬混编4D炭纤维预制体为增强体，采用沥青液相浸渍／炭化法制备了4D—C／C复合材料，研究了材料z向（炭棒方向）高温弯曲行为及损伤机理。结果表明：在室温～2100℃范围，随着温度的升高，4D—C／C复合材料z向弯曲强度呈现先增加后减小的趋势。在室温～1800℃时弯曲强度呈现增加的趋势。1800℃后随着温度升高弯曲强度开始逐渐降低，但当温度达到2100℃时其弯曲强度仍比室温下稍高。在室温一2100℃范围，随着温度的升高，软硬混编预制体增强沥青基4D—C／C复合材料。向弯曲断裂应变一直呈增加的趋势，而弯曲弹性模量总体呈减小的趋势。室温下4D—C／C应力一应变曲线几乎为线性关系，高温下4D—C／C复合材料z向弯曲破坏更加趋向于非线性的破坏模式。损伤表征结果表明，随着温度的升高，材料破坏时的最大损伤逐渐增加。4D preforms woven with carbon fiber bundles and carbon rods were densified by repeated pitch impregnation and high temperature carbonization to obtain 4D-C/C composites. The high temperature flexural behavior and damage mechanism of 4D-C/C composites were examined on z （carbon rod） direction from room temperature to 2 100 ℃. As a result, with the rising of temperature, flexural strength of 4D-C/C composite on z direction has a tendency of increasing first then decreasing between room temperature and 2 100℃. Flexural strength of 4D/C/C composite is prone to increasing before 1 800℃,decreasing gradually after 1 800℃.But when temperature goes to 2 100 ℃,the flexural strength is still higher than that of room temperature. With the rising of temperature, flexural strain to failure of 4D-C/C on z direction increases continuously between room temperature and 2 100 ~C. In room tempera- ture,the curve relation of stress-strain behavior of 4D-C/C is almost linear while nonlinear in the high temperature, the character of the fraction pattern presents brittle failure while plastic failure in the high temperature.

关 键 词：软硬混编预制体 4D—C/C材料 高温弯曲行为 

分 类 号：TB332[一般工业技术—材料科学与工程]