低分子量聚碳硅烷制备3D-Cf/SiC复合材料  

PREPARATION OF 3D-C_f/SiC COMPOSITE WITH LOW-MOLECULAR POLYCARBOSILANE

作　　者：邹世钦[1] 张长瑞[1] 周新贵[1] 曹英斌[1] 

机构地区：[1]长沙国防科技大学航天与材料工程学院CFC重点实验室,长沙410073

出　　处：《复合材料学报》2005年第5期120-124,共5页Acta Materiae Compositae Sinica

基　　金："863"基金资助(2002AA305102);国防预研基金资助(41312011002)

摘　　要：研究了低分子量聚碳硅烷(PCS)通过先驱体浸渍裂解(PIP)工艺制备Cf/SiC复合材料.分析表明:PCS的数均分子量为400,活性较强,陶瓷化产率为70%左右,在1200℃基本转化为微晶态的β-SiC.分别通过3种不同升温速率制备了3D-Cf/SiC复合材料试样,其弯曲强度分别为745.2 MPa、686.7 MPa和762.5 MPa,明显高于文献报道3D-Cf/SiC复合材料弯曲强度300～500 MPa的水平.试样断口的SEM照片均显示长的纤维拔出,有良好的增韧效果,低分子量PCS裂解得到的基体比较致密.实验结果说明,低分子量PCS适合于制备3D-Cf/SiC复合材料,并且提高升温裂解速率对材料性能影响很小.3D-Cf/SiC composites were prepared with low-molecular polycarbosilane （PCS） using a precursor infiltration pyrolysis （PIP） process. The average molecular weight of active PCS is 400 （Mn）. The ceramic yield is approximately 70%, and PCS was translated into β-SiC crystal at 1200℃. The samples of 3D-Cf/SiC composites were prepared at three different heating rates. Bending strengthes were respectively 745. 2 MPa, 686. 7 MPa, and 762.5 MPa. SEM photographs of sample fracture surfaces indicate that in the micro-structures there are long fibers pulled out, and the fracture toughness is high. The matrix is close-grained. The research indicates that 3D-Cf/SiC composites with low-molecular polycarbosilane have good mechanical performance, and the low-molecular PCS fits the preparation of 3D-Cf/SiC composites by PIP process.

关 键 词：低分子量聚碳硅烷 先驱体浸渍-裂解工艺 Ct/SiC复合材料 

分 类 号：TB323[一般工业技术—材料科学与工程] TB332