氧化硅气凝胶具有极低的热导率和密度,可作为很好的隔热材料,而脆弱的力学性能限制了其在隔热领域的应用.在不影响隔热效果的前提下,通过复合陶瓷纤维可增加氧化硅气凝胶的强度及韧性.试验探索了陶瓷纤维增强氧化硅气凝胶在室温下的拉伸、压缩和剪切等基本力学性能,分别研究了300℃、600℃和900℃下复合材料纤维铺层面方向的压缩性能,并采用扫描电子显微镜对高温试样微观结构进行了观察分析.结果表明:陶瓷纤维增强氧化硅气凝胶的性能表现出方向性,弹性模量在铺层面内方向与厚度方向的数值最大相差约28倍,强度极限亦然;在室温条件下,复合材料的拉伸和压缩弹性模量不同,X、Y和Z方向拉伸模量与对应的压缩模量之比分别为1.60、1.83和0.56;高温下复合材料沿厚度方向收缩,收缩量随温度升高而增大,900℃下的最大收缩量可达10.8%;高温下复合材料铺层面内方向压缩性能随温度升高而增强.
参考文献
[1] | Kistler S S.Coherent expanded aerogels and jellies[J].Nature,1931,127(3211):741.,1931. |
[2] | 邓忠生,王珏,陈玲燕.气凝胶应用研究进展[J].材料导报,1999,13(6):47-49.Deng Zhongsheng,Wang Jue,Chen Lingyan.The development of aerogel applications[J].Materials Review,1999,13(6):47-49.,1999. |
[3] | 秦国彤,门薇薇,魏微,李大鹏.气凝胶研究进展[J].材料科学与工程学报,2005(02):293-296. |
[4] | Parmenter K E,Milstein F.Mechanical properties of silica aero gels[J].Journal of Non Crystalline Solids,1998,223(3):179-189.,1998. |
[5] | 高庆福,张长瑞,冯坚,冯军宗,姜勇刚,武纬.氧化硅气凝胶隔热复合材料研究进展[J].材料科学与工程学报,2009(02):302-306,228. |
[6] | 高庆福,冯坚,张长瑞,冯军宗,武纬,姜勇刚.陶瓷纤维增强氧化硅气凝胶隔热复合材料的力学性能[J].硅酸盐学报,2009(01):1-5. |
[7] | 孙燕涛,石多奇,杨晓光,冯坚,姜勇刚.纤维增强SiO2气凝胶复合材料压缩性能和变形机制[J].复合材料学报,2013(04):225-230. |
[8] | Toledo Fernández J A,Mendoza Serna R,Santos A,et al.Im provement of the bioactivity of organic inorganic hybrid aerogels/wollastonite composites with TiO2[J].Journal of Sol Gel Science and Technology,2008,45(3):261-267.,2008. |
[9] | de la Rosa Fox N,Toledo Fernández J A,Morales Flórez V,et al.Creep and stress relaxation of hybrid organic inorganic aero gels[J].Key Engineering Materials,2010,423:167-172.,2010. |
[10] | Lee M Y,Hofer J H,Bronowski D R,et al.Mechanical proper ties of thermal protection system materials,SAND 2005-3173[R].New Mexico:Sandia National hboratories,2005.,2005. |
[11] | European Committee for Standardization.DIN EN 12291 Me chanical properties of ceramic composites at high temperature in air at atmospheric pressure[S].Berlin:European Committee for Standardization,2003.,2003. |
[12] | American Society for Testing and Materials.ASTM D 4255/D 4255M Standard test method for in plane shear properties of poly mer matrix composite materials by the rail shear method[S].West Conshohocken,PA:ASTM International,2002.,2002. |
[13] | 王小东.纳米多孔SiO2气凝胶隔热复合材料应用基础研究[D].长沙:国防科技大学,2006.Wang Xiaodong.Base research on the application of nanoporous SiO2 aerogel based thermal insulation composites[D].Changsha:National University of Defense Technology,2006.,2006. |
[14] | Phalippou J,Despetis F,Calas S,et al.Comparison between sin tered and compressed aerogels[J].Optical Materials,2004,26 (2):167-172.,2004. |
[15] | Woignier T,Phalippou J.Mechanical strength of silica aerogels[J].Journal of Non Crystalline Solids,1988,100(1):404-408.,1988. |
上一张
下一张
上一张
下一张
计量
- 下载量()
- 访问量()
文章评分
- 您的评分:
-
10%
-
20%
-
30%
-
40%
-
50%