Improving tribological and corrosion properties of Aluminum-CNT surface nano composite fabricated via Friction Stir Processing

Poor wear resistance and low hardness of Aluminum alloy 1200 (AA-1200) limits its industrial application.In this research, Aluminum-Carbon Nano Tube (Al/CNT) surface nano composite was fabricated via Friction Stir Processing (FSP) technique. Microstructural studies illustrated that with the increase of CNT contents from 4 to 18vol.% the grain size decreased from 30±5μm in the substrate to 10±2μm in the processed zone. Microhardness evaluations indicated that dispersed CNT in the composite layer increased the hardness up to 70% of the base metal. Potentiodynamic polarization tests revealed that with the increase of CNT contents, corrosion resistance decreased, while wear resistance improved with increasing of CNT content. SEM studies showed a relatively uniform distribution of CNT in the matrix with 10vol.% of CNT, but agglomeration of CNT occurs with higher contents of CNT.

Keywords:

Aluminum , CNT , FSP , grain size , corrosion , wear