Sun Zhefei, Zhao Jun, Wang Xuchao, Cui Enzhao, Yu Hao
Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE, School of Mechanical Engineering, Shandong University, Jinan 250061, China.
National Demonstration Center for Experimental Mechanical Engineering Education, Shandong University, Jinan 250061, China.
Nanomaterials (Basel). 2020 Sep 11;10(9):1815. doi: 10.3390/nano10091815.
Graphene and nano-TiC, which have good reinforcing effects on AlO-based ceramic-tool materials, are generally used as additive phases for ceramics. In this study, nine kinds of samples were sintered, to investigate the effects of graphene and nano-TiC on the reinforcing mechanisms of AlO-based ceramics. The experimental results indicated that adding 0.5 vol% graphene and 10 vol% nano-TiC can obtain the optimum flexural strength, fracture toughness, and Vickers hardness, which were 705 ± 44 MPa, 7.4 ± 0.4 MPa m, and 20.5 ± 0.8 GPa, respectively. Furthermore, the reinforcing mechanisms of crack bridging, pull-out of graphene, and pull-out of nano-TiC are identified, which are contributed to improving the mechanical properties of ceramics. Meanwhile, other reinforcing mechanisms induced by graphene (graphene break, crack guiding, and 3D propagation) and nano-TiC (crack branching, crack deflection, and peeling) are discussed. These reinforcing mechanisms are coupled together, while decoupling is hard to work out. Thus, further quantitative studies of reinforcing effects of graphene and nano-TiC on AlO-based ceramic-tool materials are necessary to be carried out.
石墨烯和纳米TiC对AlO基陶瓷刀具材料具有良好的增强效果，通常用作陶瓷的添加相。在本研究中，烧结了九种样品，以研究石墨烯和纳米TiC对AlO基陶瓷增强机制的影响。实验结果表明，添加0.5 vol%的石墨烯和10 vol%的纳米TiC可获得最佳的抗弯强度、断裂韧性和维氏硬度，分别为705±44 MPa、7.4±0.4 MPa·m和20.5±0.8 GPa。此外，还确定了裂纹桥接、石墨烯拔出和纳米TiC拔出的增强机制，这些机制有助于提高陶瓷的力学性能。同时，还讨论了由石墨烯（石墨烯断裂、裂纹引导和三维扩展）和纳米TiC（裂纹分支、裂纹偏转和剥离）引起的其他增强机制。这些增强机制相互耦合，难以解耦。因此，有必要对石墨烯和纳米TiC对AlO基陶瓷刀具材料的增强效果进行进一步的定量研究。
