The Influence of Laser Surface Remelting on the Tribological Behavior of the ECAP-Processed AZ61 Mg Alloy and AZ61–Al₂O₃ Metal Matrix Composite

Abstract

This paper deals with the tribological study of the laser remelted surfaces of the ECAP-processed AZ61 magnesium alloy and AZ61–Al2O3 metal matrix composite with 10 wt.% addition of Al2O3 nanoparticles. The study included the experimental optimization of the laser surface remelting conditions for the investigated materials by employing a 400 W continual wave fiber laser source. Tribological tests were performed in a conventional “ball-on-disc” configuration with a ceramic ZrO2 ball under a 5 N normal load and a sliding speed of 100 mm/s. The results showed that both the incorporation of Al2O3 nanoparticles and the applied laser treatments led to recognizable improvements in the tribological properties of the studied AZ61–Al2O3 composites in comparison with the reference AZ61 alloy. Thus, the best improvement has been obtained for the laser modified AZ61–10 wt.% Al2O3 nanocomposite showing about a 48% decrease in the specific wear rate compared to the laser untreated AZ61 base material.

Keywords

• AZ61 magnesium alloy
• AZ61–Al₂O₃ composite
• laser surface remelting
• coefficient of friction
• wear rate