• 文献标题:   Unoxidized Graphene/Alumina Nanocomposite: Fracture- and Wear-Resistance Effects of Graphene on Alumina Matrix
  • 文献类型:   Article
  • 作  者:   KIM HJ, LEE SM, OH YS, YANG YH, LIM YS, YOON DH, LEE C, KIM JY, RUOFF RS
  • 作者关键词:  
  • 出版物名称:   SCIENTIFIC REPORTS
  • ISSN:   2045-2322
  • 通讯作者地址:   Sungkyunkwan Univ
  • 被引频次:   104
  • DOI:   10.1038/srep05176
  • 出版年:   2014

▎ 摘  要

It is of critical importance to improve toughness, strength, and wear-resistance together for the development of advanced structural materials. Herein, we report on the synthesis of unoxidized graphene/alumina composite materials having enhanced toughness, strength, and wear-resistance by a low-cost and environmentally benign pressure-less-sintering process. The wear resistance of the composites was increased by one order of magnitude even under high normal load condition (25 N) as a result of a tribological effect of graphene along with enhanced fracture toughness (K-IC) and flexural strength (sigma(f)) of the composites by similar to 75% (5.60 MPa.m(1/2)) and similar to 25% (430 MPa), respectively, compared with those of pure Al2O3. Furthermore, we found that only a small fraction of ultra-thin graphene (0.25-0.5 vol%, platelet thickness of 2-5 nm) was enough to reinforce the composite. In contrast to unoxidized graphene, graphene oxide (G-O) and reduced graphene oxide (rG-O) showed little or less enhancement of fracture toughness due to the degraded mechanical strength of rG-O and the structural defects of the G-O composites.