Effective load transfer at CNT/matrix interface by intentional formation of nanocarbides on the surface of carbon nanotubes.

本文综述了在多壁碳纳米管-铜复合材料中添加少量铬在碳纳米管上制备碳化铬纳米结构的方法。通过溶质铬原子向碳纳米管中缺陷的扩散，在化学处理的碳纳米管的侧壁上外延生长了碳化物单晶。碳化物具有岛状形貌，最大尺寸为几百纳米。所生成的碳化铬纳米结构的物相主要是Cr7C3，用透射电子显微镜的纳米束衍射模式进行了电子束衍射。特别是，在径向拉链位置形成的碳化铬纳米结构连接到多壁碳纳米管的最外壁和一些内壁，这将提高多壁碳纳米管的承载能力，因为内壁有助于载荷的传递，这对改善复合材料的力学性能和热机械性能非常有效。

This report summarizes the fabrication of chromium (Cr) carbide nanostructures on multiwalled carbon nanotubes (MWCNTs) in a MWCNT-copper (Cu) composite by adding small amounts of Cr. A single nanocrystal of carbide was epitaxially grown on the sidewallof chemically treated MWCNTs through the diffusion of solute Cr atoms to defects in the MWCNTs. Carbide has an island-shaped morphologywith a maximum size of several hundred nanometers. The phase of the generated Cr carbide nanostructures was mostly Cr7C3,as determined by electron beam diffraction using the nanobeam diffraction mode of a transmission electron microscope. In particular, theCr carbide nanostructures formed at radially unzipped sites were connected to the outermost wall and some inner walls of the MWCNTs.This is expected to increase the load-bearing capacity of the MWNCTs because the inner walls contribute to the load transfer, which isvery effective for improving the mechanical and thermomechanical properties of the composites.