【摘要】 采用真空热压烧结工艺,在2150℃及30 MPa压制压力条件下,保温30 min制备了石墨烯/B4C陶瓷基复合材料。采用拉曼光谱仪、X射线衍射仪和扫描电镜分析了复合材料的物相组成和显微结构,通过测量陶瓷的相对密度、硬度和弯曲强度,研究了氧化石墨烯添加量对B4C烧结行为和力学性能的影响。结果表明:复合材料的相对密度随着石墨烯含量的增加先增加而后降低。当氧化石墨烯含量为3. 0wt%时,复合材料的力学性能达到最大值,其抗弯强度为547 MPa,断裂韧性为4. 50 MPa·m^1/2,裂纹偏转以及石墨烯拔出是材料力学性能提升的原因;与此同时,该复合材料的电导率达到1. 0 S/m以上,达到了电加工所需的电导率水平。更多还原

【Abstract】 Graphene/B₄C composites were fabricated by hot-pressing sintering in vacuum at 2150 ℃ for 30 min under a uniaxial pressure of 30 MPa. The phase composition and microstructure of the composites were analyzed by XRD,RAMAN and SEM. The effects of graphene oxide（ GO） additions on the sintering performance and mechanical properties of B₄C were studied by measuring the density,hardness,bending strength and fracture toughness of the composites. The results show that the relative density of the composites increases first and then decreases with the increase of GO content. With3. 0 wt% content of GO,the composite get to the best mechanical properties,of which the flexural strength and fracture toughness reaches up to 547 MPa and 4. 50 MPa·m^1/2,respectively. This can be attributed to the dissipation function of energy in the process of the crack deflection and graphene pullout. Moreover,the electrical conductivity of the composites reaches above 1. 0 S/m,which meets the electrical processing requirements.更多还原