炭布叠层穿刺C/C复合材料螺栓连接件微观组织和力学性能

摘要

以炭布叠层穿刺结构作为预制体,通过热梯度化学气相沉积(TCVI)工艺,制备了C/C复合材料,并沿不同纤维增强方向加工出C/C复合材料螺栓.考虑到机械加工对C/C复合材料性能的损伤,提出了C/C复合材料螺栓力学性能的测试方法,通过自行设计的模具,对所制备连接件的力学性能进行了测试表征,并利用偏光显微镜(PLM)和扫描电子显微镜( SEM),对C/C复合材料螺栓的微观组织结构及断口形貌进行了分析.结果表明,所制备的螺栓具有较好的抗拉和抗剪能力,沿平行于炭布X-Y面方向(xy向)加工的C/C复合材料连接件具有较高的力学性能,螺柱的抗拉强度和剪切强度分别为52.3 MPa和49.8 MPa,圆柱销剪切强度为52.2 MPa.%Using laminated carbon cloth with punctured carbon fibers as preform, high density C/C composites were prepared by thermal gradient chemical vapor infiltration (TCVI) technology. C/C composites bolts were fabricated by machining processing along different fiber reinforced direction. The methods were proposed to evaluate mechanical properties of C/C composite mechanical joints and the mechanical properties were measured by special clamps. The microstructure and rupture morphology were observed and analyzed by polarization microscope ( PLM ) and scanning electron microscope ( SEM) . The results show that C/C composite bolts machined along the direction of carbon cloth (xy direction) have better mechanical properties. The tensile strength and shear strength of C/C composite bolts are 52. 3MPa and 49. 8MPa respectively. The shear strength of C/C composite straight pin is 52. 2 MPa.