CNTs修饰及其增强Cu基复合材料的研究

碳纳米管(CNTs)经不同方法修饰后,通过湿式球磨法制备2%-CNTs/Cu(体积分数,下同)复合粉体,再通过H2退火-冷压烧结工艺制得2%-CNTs/Cu复合材料。结果表明:球磨短切后CNTs的长度变短,端口被打开,无定型碳增多,而混酸纯化后CNTs表面的杂质完全被除去,引入大量含氧活性基团;湿式球磨法可以将CNTs嵌入Cu基体中,并与其紧密结合形成片状复合结构,再经H2退火处理后得到超细晶复合粉体;短切和纯化都有利于CNTs在Cu基体的分散与结合,其中短切CNTs纯化后制得复合材料的抗拉强度和维氏硬度最高,分别为296MPa和139.8HV,较基体提高了123.6%和42.9%,归因于细晶强化和载荷传递。

CNT s Modified and Enhanced Cu Matrix Composites

The composite powders of 2%‐CNTs were prepared by wet ball milling and hydrogen annea‐ling treatment‐cold pressing sintering was used to consolidate the ball milled composite powders with different modifications of the CNTs .The results show that the length of the CNTs is shortened ,ports are open ,and amorphous carbon content is increased by ball milling .And after a mixed acid purifica‐tion ,the impurity on the surface of the CN T s is completely removed ,and a large number of oxygen‐containing reactive groups are introduced ;the most of CNTs can be embedded in the Cu matrix and the CNTs have a close bonding with the Cu matrix ,forming the lamellar composite structure ,then , ultrafine‐grained composite powders can be obtained by hydrogen annealing treatment .Shortening and purification of the CNTs are both good for dispersion and bonding of CNTs in the Cu matrix ,and the tensile strength and hardness of the composites after shortening and purification reaches the highest , and is 296M Pa and 139 .8HV respectively ,compared to the matrix ,up to 123 .6% in tensile strength and 42 .9% in hardness ,attributed to the fine grain strengthening and load transferring .