Hardness Improvement of Aluminum Reinforced with Carbon Nanotubes through Forging and Friction Surfacing Process

Abstract

This research deals with the improvement of hardness property on the composite material made from aluminum matrix reinforced with carbon nanotubes (Al-CNTs). There were two experiments conducted to enhance hardness property; forging and friction surfacing process. An axial mechanical force forged the Al-CNTs composite up to 40% of height of a cylindrical aluminum. A thermo-mechanical force was also applied in producing Al-CNTs coating by the friction surfacing process using Al-CNTs composite rod. Then, the hardness property obtained from these two processes was investigated. Results of the experiments showed that the hardness of Al-CNTs after the forging process improved 40-50% due to high amount of dislocation during forging which avoids deformation. This was indicating that 1 wt% CNTs does not decrease the hardenability of aluminum alloys. Meanwhile, the hardness Al-CNTs coating was not altered too much by the process of friction surfacing. This is becaused that the homogenous dispersion of the CNTs have occurred during the stir casting process.