强脉冲下C包裹Cu-SiC颗粒增强AZ91合金组织及力学性能  

Modification of AZ91 Mg-Alloy with Cu-SiC Particles Wrapped in Graphite and Doped by High Current Pulsed Electron Beams Irradiation

作　　者：李志刚 郭世海[2] 庚贵弘 魏国青 Li Zhigang;Guo Shihai;Geng Guihong;Wei Guoqing(Department of Mechanical and Electrical Engineering,Wuhai Vocational and Technical College,Wuhai 016000,China;Research Institute of Iron and Steel,Beijing 100081,China;School of Mechanical Engineering,North University for Nationalities,Yinchuan 750021,China)

机构地区：[1]乌海职业技术学院机电工程系,乌海016000 [2]钢铁研究总院,北京100081 [3]北方民族大学机械工程学院,银川750021

出　　处：《真空科学与技术学报》2020年第12期1214-1218,共5页Chinese Journal of Vacuum Science and Technology

基　　金：国家自然科学基金项目(51731002)。

摘　　要：通过强脉冲处理技术制得C包裹Cu-SiC/AZ91复合材料,在AZ91熔体内加入适当含量的Cu-SiC颗粒来实现合金增强的效果,同时表征了复合材料的显微组织结构。研究结果表明:加入Cu-SiC能够使SiC和AZ91形成更充分润接触。采用强脉冲进行处理时,Al_(4)C_(3)和α-Mg主要出现于Mg2Si枝晶边缘区域,Al_(4)C_(3)发生了快速形核,形成细小组织,进而降低了SiC的偏聚程度,从而获得更均匀的组织结构。Cu-SiC可以使AZ91基材力学强度获得显著提高,引起伸长率减小。施加强脉冲有助于提高晶粒细化,生成更过Mg_(2)Si相,能有效提高合金的拉伸强度和伸长率。在Cu-SiC/AZ91试样内形成致密组织,属于韧性和准解理断裂混合断裂方式。施加强脉冲后,Cu-SiC/AZ91试样断口韧窝表现的更为细小。加入Cu-SiC颗粒后AZ91合金硬度获得了小幅提升,施加强脉冲后Cu-SiC/AZ91合金硬度发生了更明显提升。AZ91 Mg-alloy,an advanced aerospace material,was modified with the Cu-SiC particles wrapped in graphite and doped into molten AZ91 by high current pulsed electron beam irradiation.The influence of the doping of Cu-SiC particles and e-beam irradiation on the microstructures and mechanical properties was investigated.The results show that the e-beam irradiation and Cu-SiC doping had a major impact.Specifically,the modified compact AZ91 alloy comprised the dendrite Mg_(2)Si grains surrounded at the edges byα-Mg and Al_(4)C_(3) clusters;the e-beam irradiation weakened the segregation,improved the uniform distribution and wetting contacts of Cu-SiC particle,refined the grain-size,significantly enhanced the hardness and tensile strength;and the e-beam irradiation of the added Cu-SiC accounted for the formation of Mg_(2)Si,resulting in the increases of the tensile strength and elongation-ratio of AZ91 Mg-alloy.The ductile and quasi-cleavage modes were the hybrid fracture mechanisms.

关 键 词：Cu-SiC/AZ91复合材料 强脉冲 晶粒细化 力学性能 

分 类 号：TG291[金属学及工艺—铸造]