Interactions between Carbon Nanotubes and Nickel

 

Speaker : Prof. Raj Banerjee

Date &Time : 2009. 6. 24 (Wed), 14:00

Place : 신소재공학과 #2427강의실

 

Abstract

 

Interactions between Carbon Nanotubes and Nickel

 

   In recent years there has been a substantial amount of research interest on metal-matrices reinforced with carbon nanotubes. The primary focus of our studies in this area has been the interaction between these nanotubes and the metal. Towards this end, we have been investigating two types of systems; bulk composites based on multi-walled carbon nanotubes (MWCNT) dispersed in a nickel matrix, processed using the laser-engineered net shape (LENS) processing technique, and, vertically-aligned carbon nanotubes coated with vapor deposited nickel.

  The advantage of using LENS is that that while using a powder feedstock, the composites are processed via a liquid metal route involving rapid solidification. The present study focuses on two aspects, the survivability of nanotubes during melt processing using LENS in a liquid nickel matrix, and the structure and chemistry of the interface between the nanotubes and metal matrix. Furthermore, the stability of MWCNT versus graphite powders in liquid nickel have been compared by processing both types of composites under identical conditions. These composites have been characterized in detail using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and, micro-Raman spectroscopy.

  The microhardness and the wear resistance of the MWCNT reinforced composites have also been studied and these results will also be presented. The second part of this presentation will focus on vertically-aligned carbon nanotubes coated with sputter-deposited nickel. In this case the nanotubes act as templates for the nucleation and growth of nickel nanocrystals. The stabilization of a metastable hexagonal nickel-carbon phase in the nanocrystals will be discussed based on results of TEM and 3D atom probe studies.