Enhancing the Surface Properties of Aluminium Alloy 6061 by Laser Cladding with DWCNTs and MWCNTs using an Automated Pulsed Nd:YAG Laser

Abstract

Industrial applications of nanomaterial in particular carbon nanotubes ??(CNTs) have increased from ?various viewpoints, such as, high performance, ?energy saving, cost saving, and environmental concerns. ?Laser cladding ?technique has been used successfully to modify the surface properties of ?materials, i.e., ?improving their wear and corrosion resistance. This work ?involves cladding aluminum alloy (Al 60601) with ?different types of carbon ?nanotubes (multi-walled carbon nanotubes (MWCNTs) and double ?walled ?carbon nanotubes (DWCNTs)) by an automated pulsed Nd:YAG laser. This ?was achieved by ?controlling selected cladding parameters which are laser ?power, pulse duration, and working frequency. The ?experimental ?investigation included microhardness, energy dispersive X-ray, corrosion ?resistance and ?microstructure topography by scanning electron microscope. ?The optimum estimated laser parameters for ?achieving the best results at ?spot diameter of 3 mm were (peak power of 3.1 kW, pulse duration of 16 ?msec ??(3 msec as pre heating and 13 msec as the main action time of the ?pulse) and working frequency of 1.5 Hz.? Results indicated that laser cladding of Al 6061 using DWCNT ?enhanced three of the most important of ?surface properties which are ?hardness, abrasive wear resistance and corrosion resistance more than did ?the ?MWCNTs. The distribution of the MWCNTs on the surface of Al 6061 ?is better than that for the DWCNTs ?but its penetration is less.?

Keywords: Laser cladding, CNTs, DWCNTs, MWCNTs, AL6061.