添加SiC微粉对硅树脂先驱体转化3D C_f/Si-O-C材料性能的影响

BEffect of Adding SiC Powder on the Properties of Carbon Fiber Reinforced Si-O-C Composites Fabricated Via Precursor Pyrolysis

以三维碳纤维织物和廉价的硅树脂为原料,采用先驱体转化工艺制备3D Cf/Si-O-C材料,考察了浸渍液中添加SiC填料对材料微观结构、力学性能和抗氧化性能影响。结果表明:添加适量的SiC填料有助于减少基体孔隙,改善界面结合,从而提高材料的力学性能;而SiC含量过高时,容易在材料内部形成闭孔,从而导致材料力学性能下降。当SiC微粉含量为18.2%时,材料具有最好的力学性能,弯曲强度和断裂韧度分别为421.3MPa和13.0 MPa.m1/2;而材料的抗氧化性能随着SiC微粉含量的增加而增加,当SiC微粉含量为25.0%时,材料的弯曲强度保留率最高,达到了89.5%。

A study is presented on a three Dimensional carbon fiber cloth reinforced silicon oxycarbide （3D Cf/Si-O-C） composites with low cost silicon resin as precursors and 3D Cf as reinforcement. Effects of adding SiC powder（SiCp） on the structure, mechanical properties and anti-oxidation properties of 3D Cf/Si-O-C composites were investigated. The results showed that adding SiCP filler could reduce the porosity and improve the interface bonding, therefore increase the properties of composites. But when the content was excessive, it was difficult to dense the matrix of composites at the further cycles and pores existed in the matrix. As a result, the mechanical properties of the composites decreased. It was found that when fabricated with 18.2 weight percent SiCp, the composites exhibited the highest mechanical properties, and the flexural strength and fracture toughness reached 421.3MPa and 13.0 MPa·mT1/2, respectively. Meanwhile, the anti-oxidation properties were improved with the increase of the SiCp content. When fabricated with 25.0 weight percent SiCp, the composites exhibited best oxidation resistance properties, and the composites retained 89.5% of original flexural strength.