离心成型工艺制备改性碳纤维增强 HA复合材料

摘要

The carbon fibers treated by HCl were coated with HA layers using sol-gel technology and then used to fabricate the treated C-fibers reinforced HA composites by centrifugal slip casting technology.The treated technologies of C-fibers were studied,micro-morphologies of the untreated and treated C-fibers were observed, the effect of the solid content of HA slurries on mass segregation during centrifugal process was analyzed,and mechanical properties of sintered composites were measured.The results show the carbon fibers after HCl dis-posal and dip in HA sol have a compact layer which has better contact with HA matrix.After centrifuged at 2 860 g acceleration,the green compacts have uniform density.SEM observation shows the sintered composites have compact microstructure and no obvious mass segregation phenomenon.The treated CF/HA composites prepared by centrifugal slip casting have the highest bending strength of 93.5 MPa and flexural toughness of 1.96 MPa•m1/2 ,respectively,when the contents of C-fibers was 2% and 2.5wt%.%先对碳纤维进行 HCl 预处理,然后通过溶胶-凝胶技术在预处理后碳纤维表面涂覆 HA 涂层,最后利用离心成型技术制备改性碳纤维增强 HA复合材料.重点研究碳纤维的改性工艺,观察改性前后碳纤维表面的微观形貌,分析 HA 浆料固相含量对离心过程中物质分离现象的影响,测量不同碳纤维含量下烧结产物的抗弯强度和断裂韧度.研究结果表明,经过HCl和提拉HA溶胶复合处理的碳纤维表面具有1层致密的、与基体结合性能较好的膜层.固相含量为50％(质量分数)HA 浆料在2860 g 加速度下离心后所得生坯密度均匀,SEM观察表明烧结产物致密,没有明显的物质分离现象.当碳纤维含量为2％(质量分数)时,离心成型制备的改性碳纤维/HA 复合材料的抗弯强度达到最大值93．5 MPa；当碳纤维含量为2．5％(质量分数)时,该复合材料的断裂韧度达到最大值1．96 MPa•m1/2.