Optimization of Surface Mechanical Properties and Characterization of AZ31B/CNT Nano-composite through Friction Stir Processing (FSP) using Response Surface Methodology (RSM) Design of Experiment

In this paper, the optimization of the surface composite of Mg AZ31B-carbon nanotub(CNT) via friction stir processing was investigated. Then, the most effective process parameters such as transverse speed, rotational speed, CNT weight percent and welding passes were studied by Response Surface Methodology (RSM) design of experiment. The specimens were also characterized by micro-hardness, tensile, shear punch and pin on disk dry sliding wear tests. The optimization results of hardness and weight reduction responses showed that the best conditions would be achievable with a transverse speed of 24 mm/min, rotational speed of 660 rpm, 4wt.% CNT and 3 welding passes. Moreover, fracture analysis of the surfaces proved a uniform distribution of CNTs in the matrix resulted in higher tensile and shear strength.