摘要
石墨烯已被广泛应用于陶瓷材料的增韧,如何实现其在陶瓷材料基体的良好分散性是提高其增韧效率的瓶颈问题。本研究通过放电等离子烧结,制备了二维石墨烯(G)和一维碳化硅纳米线(SiC_(nw))协同增韧WC陶瓷材料;优化了烧结温度、保温时间及施加压力;重点研究了石墨烯和碳化硅纳米线在促进陶瓷材料致密化、微观结构演变及性能提升方面的协同作用。结果表明:采用60 MPa压强,在1900℃保温15 min,WC-0.15wt.%G-0.45wt.%SiC_(nw)可获得最优力学性能,硬度、抗弯强度和韧性分别为25.6 GPa、1499 MPa和11.6 MPa·m^(1/2)。主要增韧机理为:G/SiC_(nw)裂纹偏转、桥联和拔出。本研究有助于高强韧陶瓷基复合材料的发展。
The aggregation of low-dimensional nanofillers in the host ceramic matrix significantly discounted their reinforcing efficiency.Herein,employing two-dimensional graphene(G) and one-dimensional SiC nanowire(SiC_(nw)),WC-G-SiC_(nw) ceramic composites were prepared through spark plasma sintering.The effects of sintering temperature,soaking time and pressure on the mechanical properties of the WC-based composites were reported.The influence of graphene and SiC_(nw) on the densification,microstructure and mechanical properties of the ceramic composites were investigated.The experimental results demonstrated that excellent mechanical properties were achieved for WC-0.15 wt.% G-0.45 wt.% SiC_(nw) prepared through sintering at 1900 ℃ for 15 min holding time and 60 MPa pressure,with a hardness of 25.6 GPa,a flexural strength of 1499 MPa and a fracture toughness of 11.6 MPa·m^(1/2).The toughening mechanisms were mainly the combination of G and SiC_(nw) induced crack deflection,bridging and pullout.This study provided a simple toughening method in developing high-performance ceramic composites.
作者
沈学会
徐楠
苏豪
何向平
何建群
SHEN Xue-hui;XU Nan;SU Hao;HE Xiang-ping;HE Jian-qun(School of Mechanical and Electronic Engineering,Shandong Jianzhu University,Jinan 250101,China;School of Mechanical Engineering,Qilu University of Technology(Shandong Academy of Sciences),Jinan 250353,China;Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education,Dalian University of Technology,Dalian 116024,China)
基金
Project(ZR2023ME104) supported by the Shandong Provincial Natural Science Foundation,China。