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.
参考文献
| [1] | 姜开宇,李贺军,侯向辉,李克智.轴对称C/C复合材料件等温CVI过程的数值模拟研究[J].西北工业大学学报,2000(04):665-668. |
| [2] | 张明瑜,黄启忠,谢志勇,苏哲安,尹彩流,黄伯云.多元耦合场CVI法快速致密化炭/炭复合材料研究[J].功能材料,2006(10):1623-1626. |
| [3] | 黄伯云;熊翔.高性能炭/炭航空制动材料的制备技术[M].长沙:湖南科学技术出版社,2007 |
| [4] | 焦健,史一宁,邱海鹏,孙明,李秀倩,罗京华.高性能连续碳纤维增强碳化硅复合材料的制备及其高温力学性能的研究[J].功能材料,2011(z3):401-404. |
| [5] | Hejun Li;Aijun Li;Ruicheng Bai .Numerical simulation of chemical vapor infiltration of propylene into C/C composites with reduced multi-step kinetic models[J].Carbon: An International Journal Sponsored by the American Carbon Society,2005(14):2937-2950. |
| [6] | Li AJ;Deutschmann O .Transient modeling of chemical vapor infiltration of methane using multi-step reaction and deposition models[J].Chemical Engineering Science,2007(18/20):4976-4982. |
| [7] | Modeling and simulation of materials synthesis: Chemical vapor deposition and infiltration of pyrolytic carbon[J].Composites science and technology,2008(5):p.1097. |
| [8] | Li Aijun;Zhang S;Reznik B et al.Chemistry and kinetics of chemical vapor deposition of pyrolytic carbon from eth-anol[J].Proceedings of the Combustion Institute,2011,33(02):1843-1850. |
| [9] | Weigang Zhang;Klaus J.Huttinger .Chemical vapor infiltration of carbon - revised Part I: Model simulations[J].Carbon: An International Journal Sponsored by the American Carbon Society,2001(7):1013-1022. |
| [10] | Zhang WG.;Hu ZJ.;Huttinger KJ. .Chemical vapor infiltration of carbon fiber felt: optimization of densification and carbon microstructure[J].Carbon: An International Journal Sponsored by the American Carbon Society,2002(14):2529-2545. |
| [11] | 张伟刚.化学气相沉积:从烃类气体到固体炭[M].北京:科学出版社,2007 |
| [12] | Becker A.;Huttinger KJ.;Hu Z. .A hydrogen inhibition model of carbon deposition from light hydrocarbons[J].Fuel,2000(13):1573-1580. |
| [13] | John Ibrahim;Samuel Paolucci .The modeling of realistic chemical vapor infiltration/deposition reactors[J].International Journal for Numerical Methods in Fluids,2010(5):473-516. |
| [14] | John Ibrahim;Samuel Paolucci .Transient solution of chemical vapor infiltration/deposition in a reactor[J].Carbon: An International Journal Sponsored by the American Carbon Society,2011(3):915-930. |
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