石墨烯对铸造AZ91合金微观组织及力学性能的影响  

Effect of graphene on microstructure and mechanical properties of cast AZ91 alloy

作　　者：王殿君 梁英 WANG Dianjun;LIANG Ying(Modern Manufacturing Engineering Institute,Heilongjiang Institute of Technology,Jixi 158100,Heilongjiang,China;Library,Heilongjiang Institute of Technology,Jixi 158100,Heilongjiang,China)

机构地区：[1]黑龙江工业学院现代制造工程学院,黑龙江鸡西158100 [2]黑龙江工业学院图书馆,黑龙江鸡西158100

出　　处：《航空材料学报》2024年第6期26-32,共7页Journal of Aeronautical Materials

基　　金：黑龙江省自然科学基金联合引导项目(LH2022E103);黑龙江工业学院科研启动经费资助项目。

摘　　要：晶粒细化对提升镁合金的力学性能具有重要意义。本研究采用预分散结合重力铸造的方法成功制备了石墨烯增强AZ91的复合材料。采用OM,SEM,TEM等对GNP/AZ91复合材料进行微观组织表征。结果表明:随着GNP含量的增加,AZ91合金的晶粒尺寸逐渐减小。当添加1%(质量分数,下同)GNP时,AZ91合金的晶粒尺寸由415μm减小到86μm,其细化效率为79%;通过TEM观察发现并揭示GNP对AZ91合金的细化机制,主要为GNP与AZ91熔体中Al元素发生原位反应得到Al_(4)C_(3)相,能够促进α-Mg晶粒的异质形核,从而取得显著的晶粒细化效果;当GNP的含量增加到0.5%后,AZ91合金获得最佳的力学性能,其UTS、YS和EL达到了150、96 MPa和2.1%,较AZ91合金,分别提高34%、32%和91%。Grain refinement plays an important role to enhance the mechanical properties of magnesium alloys.In this work,graphene-reinforced AZ91 composites were successfully prepared by pre-dispersion combined with gravity casting method.The microstructure of the GNP/AZ91 composites was characterized using OM,SEM,TEM,etc.The results show that the grain size of AZ91 alloy gradually decreases with the increase of GNP content.When 1%GNP is added,the grain size of AZ91 alloy is reduced from 415μm to 86μm,with the refinement efficiency of 79%.It is found and revealed through TEM observation that the refining mechanism of GNP on AZ91 alloy is mainly Al_(4)C_(3)phase obtained by in-situ reaction of GNP with Al element in AZ91 melt,which can promote the heterogeneous nucleation ofα-Mg grains,thus achieving significant grain refinement effect.When the GNP content is increased to 0.5%,the best mechanical properties are obtained for AZ91 alloy with the UTS,YS and EL reaching 150,96 MPa and 2.1%,the improvement of 34%,32%and 91%respectively compared to AZ91 alloy.

关 键 词：晶粒尺寸 AZ91合金 力学性能 晶粒细化 

分 类 号：V252.2[一般工业技术—材料科学与工程] TG111.4[航空宇航科学与技术—航空宇航制造工程]