【摘要】 以硼改性酚醛树脂作为连接剂的主要成分,添加微米B₄C粉、纳米SiO₂粉和微米Mo粉作为填料,采用反应成形连接法连接C/C复合材料和C/C-Si C复合材料,并将连接件在300¹ 400℃真空环境中热处理30 min。在室温环境下测量连接件的连接强度,计算不同温度下热处理后的强度保留率,并观察与分析连接层以及经连接强度测试后的断口形貌和元素分布。结果表明,连接件在1 200℃下热处理后,连接强度保留率取得极大值97.8%,连接层结构致密,孔洞、裂纹等缺陷较少;母材与胶层的界面处发生了C,O,Si,B和Mo元素的扩散;胶层中生成熔点及硬度都很高的Mo B和Si C,Mo B作为增强体与硼改性酚醛树脂裂解生成的玻璃碳形成复相陶瓷,从而提高连接件的强度保留率。更多还原

【Abstract】 The joining of C/C to C/C-SiC was studied by the reactive process using boron-modified phenolic resin（BPF） with micro-size B₄C, nano-size SiO₂ and micro-size Mo powders as additives. The joints were heat-treated at various temperatures ranged from 300 ℃ to 1 400 ℃ in vacuum for 30 min. The strength of the joints before and after the heat treatment was measured, and retained strength was calculated. Microstructures and elemental distributions of interfacial area were observed and analyzed. The experimental results show that the maximum retained strength of the joints is obtained to be 97.8% after the heat treatment at 1 200 ℃. The interlayer of the joints is uniform and densified. There are no obvious pores or cracks at the interfaces. The diffusions of C, O, Si, B and Mo elements take place at the interfacial area. In addition, Mo B and Si C which possess high melting points and high hardness form during the heat treatment, and can serve as reinforcements in the glassy carbon formed by the pyrolysis of BPF. Therefore, the retained strength of the joints is enhanced.更多还原