热挤压石墨烯/Al基复合材料的组织及性能研究  

Investigation on the microstructure and properties of hot extruded graphene/Al matrix composite

作　　者：张辉[1,2] 裴东杰[3] 牛炳博 ZHANG Hui;PEI Dongjie;NIU Bingbo(School of Mechanical Engineering,Zhengzhou University of Science&Technology,Zhengzhou 450064,China;School of Mechanical and Engineering,Zhengzhou University,Zhengzhou 450001,China;School of Materials Science&Engineering,Zhengzhou University,Zhengzhou 450001,China;Zhengzhou Advanced Manufacturing Engineering Research Center of Key Parts for Dental Implant,Zhengzhou 450001,China)

机构地区：[1]郑州科技学院机械工程学院,河南郑州450064 [2]郑州大学机械与动力工程学院,河南郑州450052 [3]郑州大学材料科学与工程学院,河南郑州450052 [4]郑州市义牙种植关键零部件先进制造工程研究中心,河南郑州450064

出　　处：《粉末冶金工业》2023年第5期57-62,共6页Powder Metallurgy Industry

基　　金：河南省科技重点科技攻关项目(212102210348)。

摘　　要：随着科技的不断发展,为满足军工、航空航天、汽车、电子工业等对铝合金的性能提出的更高的性能、功能及结构等需求,Al基复合材料具有高比强度、高比刚度、低密度、低热膨胀系数、高耐磨性,由于其优异的力学性能及良好的可加工性成为该领域的关键新型材料。实验采用粉末冶金技术制备了石墨烯质量分数为1%的石墨烯/Al基复合材料,通过扫描电镜(SEM),高分辨透射电镜(HRTEM)和拉伸试验机表征了烧结态和挤压态石墨烯/Al基复合材料的微观组织,拉伸性能和断口形貌,系统性研究了热挤压前和热挤压后Al基复合材料中石墨烯纳米片的分布状态,进而探明了热挤压工艺对石墨烯/Al基复合材料组织和性能的影响。结果表明:挤压态石墨烯/Al基复合材料的组织均匀致密,缺陷和孔洞数量明显较烧结态大幅降低。超声分散和热挤压工艺有效抑制了石墨烯与Al基体的有害界面反应。挤压态石墨烯/Al基复合材料的抗拉强度和伸长率为161.34 MPa和23.57%,较烧结态(124.41 MPa,20.78%)分别提高29.7%和13.5%。断口形貌显示烧结态石墨烯/Al基复合材料的断口韧窝小并且浅,撕裂棱光亮,而挤压态石墨烯/Al基复合材料的韧窝大而深,且大小不一,同时存在断裂的石墨烯和较深的脱落坑。With the continuous development of science and technology,in order to meet the requirements of military,aerospace,automobile and electronic industries for higher performance,function and structure of aluminum alloy,Al matrix composites with high specific strength,high specific stiffness,low density,low thermal expansion coefficient and high wear resistance have become key new materials in this field because of their excellent mechanical properties and processability.In this paper,the graphene/Al matrix composites with a mass fraction of GO being 1%were prepared by the powder metallurgy.The microstructure,mechanical properties and fracture morphologies of the sintered and extruded composites were characterized by scanning electron microscopy(SEM),high-resolution transmission electron microscopy(HRTEM)and tensile testing machine.The distribution of graphene nanosheets in Al-based composites before and after hot-extrusion was systematically studied,and then the influence of hot-extrusion process on the structure and properties of graphene/Al-based composites was ascertained.The results show that the structure of the extruded graphene/Al matrix composite is uniform and dense,and the number of defects and pores is significantly reduced compared with the sintered state.Ultrasonic dispersion and hot extrusion process effectively suppressed the harmful interfacial reaction between graphene and Al matrix.The tensile strength and elongation of the extruded graphene/Al matrix composite is 161.34 MPa and 23.57%,which were 29.7%and 13.5%higher than those of the sintered state(124.41 MPa,20.78%),respectively.The fracture morphology shows that the fracture dimples of the sintered graphene/Al matrix composite are small and shallow,and the tear edges are bright.However,the dimples of extruded graphene/Al matrix composite are large and deep,with different sizes,and there are fractured graphene and deep detachment pits at the same time.

关 键 词：粉末冶金 石墨烯/Al基复合材料 热挤压 界面结构 断口形貌 

分 类 号：TB333[一般工业技术—材料科学与工程]