搅拌摩擦加工制备Nano-ZrO2增强AZ31镁基复合材料及其力学性能分析  

Preparation and Mechanical Properties of Nano-ZrO2 Reinforced AZ31 Magnesium Matrix Composites by Friction Stirring Processing

作　　者：陈洪美[1] 廖斯恩 李晓文 张家齐 陈书锦[1] 金云学[1] Chen Hongmei;Liao Si'en;Li Xiaowen;Zhang Jiaqi;Chen Shujin;Jin Yunxue(College of Materials Science and Engineering,Jiangsu University of Science and Technology,Zhenjiang 212003,China)

机构地区：[1]江苏科技大学材料科学与工程学院,江苏镇江212003

出　　处：《稀有金属》2020年第3期273-280,共8页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51301077);江苏省自然科学基金项目(BK20130470);中国博士后科学基金项目(2017M611748);江苏省高校优势学科建设工程项目资助。

摘　　要：以AZ31镁合金为基体,纳米二氧化锆(Nano-ZrO2)为增强体,通过高转速搅拌摩擦加工工艺在AZ31镁板上制备Nano-ZrO2/AZ31复合材料。利用透射电镜(TEM)、扫描电镜(SEM)及能谱仪(EDS)观察试样截面及拉伸断口的微观形貌、元素组成及分布;采用拉曼光谱仪对材料成分以及微区成分分布进行分析;通过超景深显微镜、硬度计和万能试验机,分析复合材料中晶粒大小、硬度及拉伸性能。结果表明:利用高转速搅拌摩擦加工技术可以制备出增强相分布均匀的Nano-ZrO2/AZ31复合材料。经过搅拌摩擦加工后,焊核区的晶粒相比母材晶粒得到明显的细化,其截面硬度比母材硬度提高了23.4%,符合弥散强化规律。并且,所制备出含不同增强体体积分数(4.29%,2.86%及1.42%)的复合材料中,增强体体积分数为2.86%的复合材料抗拉强度最高,达到168.67 MPa,其断裂伸长率为6.64%,为韧性断裂。In this experiment,AZ31 magnesium alloy was used as the matrix,and Nano-ZrO2/AZ31 composite was prepared on the AZ31 magnesium plate by high-speed friction stir processing(FSP) while using Nano-Zirconia(Nano-ZrO2) as the reinforcement.Transmission electron microscope(TEM),scanning electron microscopy(SEM) and energy dispersive spectroscopy(EDS) were used to observe the microstructure,element composition and distribution of the cross-section,and tensile fracture of the samples.And Raman Spectroscopy was used to analyze the composition and distribution of the micro-region.In addition,Hardness Tester and Universal Testing Machine were used to analyze the grain size,hardness and tensile properties of the composite.The results showed that the Nano-ZrO2/AZ31 composite with unifonn phase distribution could be prepared by high-speed FSP.After FSP,the grains in the weld nugget area were significantly refined compared with the base metal grains,and the cross-sectional hardness was increased 23.4% than that of the base metal,which was consistent with the dispersion strengthening law.In addition,among different volume fractions of reinforcement(4.29%,2.86% and 1.42%),the composite with a volume fraction of 2.86% had the highest tensile strength with168.67 MPa and elongation at break of 6.64%,which was belonged to the ductile fracture mechanism.

关 键 词：镁基复合材料 搅拌摩擦加工 晶粒细化 

分 类 号：TG146[一般工业技术—材料科学与工程]