摘要
以CH4,BCl3,H2为原料气,采用化学气相沉积法(常压CVD)在炭纤维表面连续涂覆B4C,通过正交实验得到最佳涂覆条件;采用IR、TG-DTA、XRD等技术考察了涂层的组成、结构和形貌,并对最佳涂覆条件下炭纤维的拉伸强度进行测试。实验结果表明:当υH2/υBCl3=3.5、υBCl3/υCH4=1.7、气体总流速=160mL/min,沉积温度1100℃,走丝速度5转/min时,涂层表面有明显的一层致密物质,表面较平整,涂层纤维的氧化温度由未涂层时的350℃提高到630℃,纤维的单丝强度由未涂层时的1.93GPa提高到3.15GPa。在炭纤维表面采用化学气相沉积法涂覆B4C不仅装置简单、操作方便,而且可以明显地提高炭纤维的抗热氧化性和单丝强度。
Carbon fibers coated with B4C were made by chemical vapor deposition (CVD) technique in flowing mixture gas of H2, BCl3 and CH4. The optimum conditions were obtained by the orthogonal method. The carbon fibers before and after the coating treatment were examined using IR, TG-DTA, SEM and XRD in terms of composition, structure and morphology. The tensile strain of coated fibers was measured. The results show that the surface of the coated carbon fibers is covered with a dense and regular coating material, of which the optimum conditions are as follows:υH2/υBCl3=3.5,υBCl3/υCH4=1.7, total gas flowing rate =160 mL/min,deposition temperature=1 100 ℃and walking speed of fibers =5 loops/min. After the coating treatment, the oxidization temperature of carbon fibers increases to 630 ℃from 350 ℃before the treatment, and the tensile strain increases to 3.15 GPa in comparison to 1.93 GPa before the treatment. The coating method is simple in equipment and easy to operate, is capable of improving the anti-oxidization properties and tensile strain of carbon fibers to a great degree.
出处
《炭素技术》
CAS
CSCD
2004年第5期1-5,共5页
Carbon Techniques
关键词
炭纤维
化学气相沉积
碳化硼
Chemical vapor deposition
carbon fiber
boron carbide
