Investigating the Impact of SLM Scanning Speed on Corrosion and Wear in Al-Si-Mg Alloys

Abstract

Optimizing selective laser melting (SLM) parameters is crucial for unlocking the full potential of alloy fabrication, enabling properties to be tailored for structural strength and functional reliability in demanding applications. In this work, variations on how laser power and scanning speed influence hardness, wear resistance, and corrosion behavior were explored. To evaluate this influence, the samples were produced under different processing conditions, resulting in varying microstructural properties and porosity levels. Mechanical and electrochemical responses were then methodologically evaluated: microhardness using Vickers indentation at 0.3 kgf load, wear resistance through a pin-on-disc tribometer, and corrosion performance via open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) in 3.5 wt% NaCl solution. The results reveal that careful optimized laser parameters enhance densification and refine the eutectic Si network, consequently raising the hardness values and superior wear resistance, demonstrated by lower material loss and smoother wear tracks. Also, enhanced microstructural homogeneity produced higher noble OCP and impedance values, signifying passive layer stability. But the enormous energy input, which decreased the porosity, resulted in microstructural irregularities and residual stresses that made the alloy more vulnerable to localized corrosion. Generally, these discoveries show the necessity of proper adjustment of SLM parameters to attain a balance between mechanical strength and corrosion resistance. Hence, having an insight into the resulting process–structure–property correlations is vital for enabling AlSi10Mg alloys to perform reliably in demanding aerospace, automotive, and marine applications.