氧化钛包覆CNTs增强铝基复合材料显微组织与力学性能  

Microstructure and mechanical properties of aluminum matrix composites reinforced by TiO_(2)-coated CNTs

作　　者：何苗[1] 曾敏[1] 程婷 张莉[1] He Miao;Zeng Min;Cheng Ting;Zhang Li(School of Mechanical and Automotive Engineering,Nanchang Instituteof Science and Technology,Nanchang 330108,China)

机构地区：[1]南昌工学院机械与车辆工程学院,江西南昌330108

出　　处：《轻金属》2022年第12期38-44,共7页Light Metals

基　　金：江西省教育厅科技课题(GJJ212522);江西省教育厅科技课题(GJJ212515)

摘　　要：采用钛酸四丁酯水解法制备氧化钛包覆的碳纳米管(TiO_(2)@CNTs),并用搅拌铸造法制备了包覆氧化钛的碳纳米管增强铝基复合材料(TiO_(2)@CNTs/Al)。利用X射线衍射、透射电子显微镜、拉曼光谱和拉伸试验等研究了TiO_(2)@CNTs/Al复合材料显微组织和力学性能的影响。研究结果表明,TiO_(2)@CNTs均匀分布在铝基体中明显细化了铝基体晶粒,且包覆在CNTs表面的氧化钛可以锁定CNTs并促进CNTs和铝基体的界面结合。当添加1.5 wt.%TiO_(2)@CNTs的铝基复合材料的屈服强度和抗拉强度分别为188 MPa和238 MPa,比铝基体分别提高了62%和32%。氧化钛的引入提高了CNTs和铝基体的界面结合,使得载荷从铝基体到CNTs的高效转移。TiO2@CNTs/Al复合材料力学性能的提高主要由于细晶强化、Orowan强化、热失配强化和载荷转移强化的协同效应。Carbon nanotubes coated with titanium oxide(TiO_(2)@CNTs) were prepared by hydrolysis of tetrabutyl titanate and aluminum matrix composites(AMCs) reinforced by TiO_(2)@CNTs were prepared by stirring casting. The microstructure and mechanical properties of TiO_(2)@CNTs/Al composites were investigated by XRD, TEM, Raman spectrum, and tensile testing. The results show that the uniform distribution of TiO2@CNTs in aluminum matrix significantly refined the grain size of Al matrix, and the TiO_(2)@CNTs can lock CNTs and promote the interfacial bonding between CNTs and Al matrix. The TiO_(2)@CNTs/Al composite with 1.5 wt.% TiO_(2)@CNTs displays high mechanical properties with yield strength and ultimate tensile strength of 188 MPa and 238 MPa, which are 62% and 32% higher than those of the matrix, respectively. The better mechanical properties may be attributed to good interfacial bonding optimized by the presence of TiO_(2)nanoparticles, leading to an effective load transfer from matrix to CNTs. The improvement of mechanical properties of TiO2@CNTs/Al composite was mainly due to the synergistic effects of fine grain strengthening, Orowan strengthening, thermal mismatch strengthening and load transfer strengthening.

关 键 词：铝基复合材料 碳纳米管 TiO_(2) 显微组织 力学性能 

分 类 号：TF125.2+2[冶金工程—粉末冶金] TB333[冶金工程—冶金物理化学]