石墨烯增强铝基纳米复合材料的研究

Research of Graphene-reinforced Aluminum Matrix Nanocomposites

采用球磨和粉末冶金方法成功制备出石墨烯增强铝基纳米复合材料,命名为铝基烯合金。首次发现石墨烯纳米片的添加在保持材料良好塑性的同时,显著提高了其强度。利用OM,SEM和TEM对铝基烯合金微观组织结构进行表征,并测试其拉伸性能。结果表明:石墨烯纳米片均匀分布在铝合金基体中,与基体形成良好的结合界面,且石墨烯纳米片与铝合金基体未发生化学反应,并保留了原始的纳米片结构;铝基烯合金中石墨烯纳米片含量为0.3%(质量分数)时,铝基烯合金的平均屈服强度和抗拉强度分别达到322MPa和454MPa,较未添加石墨烯纳米片的合金分别提高58%和25%,且伸长率略有提高。基于石墨烯纳米片特殊的二维褶皱结构,讨论铝基烯合金的增强增韧行为。

Graphene-reinforced aluminum matrix nanocomposites were successfully synthesized through ball milling and powder metallurgy.The tensile strength and yield strength of graphene-reinforced aluminum matrix nanocomposites are remarkably enhanced by adding graphene nanoflakes（GNFs）.Importantly,the ductility properties are remained excellently,which is firstly found in the second phase reinforced metal matrix nanocomposites.The microstructures were observed by OM,SEM and TEM method.And the tensile properties were tested.The results show that graphene nanoflakes are effectively dispersed and well consolidate with aluminum matrix,however,chemical reactions are not observed.The original structured characteristics of graphene nanoflakes are preserved very well.The average tensile strength and yield strength of nanocomposite are 454MPa and 322MPa,respectively,which are 25％ and 58％ higher than the pristine aluminum alloy at a nanofiller mass fraction of 0.3％,while the ductility increases slightly.The relevant mechanisms of strengthening and toughening enhancement are discussed on the base of 2D and wrinkled structured properties of graphene nanoflakes.