Improvement of Mechanical Properties and Corrosion Resistance of Friction Stir Welded Joints Made of Dissimilar Aluminum Alloys Through Scandium-Enriched Alloy Powder Incorporation

Abstract

Friction stir welding (FSW) is a widely utilized process for joining aluminum alloys due to its ability to produce high-quality welds with excellent mechanical properties. In this study, the effect of adding Scandium enriched (Al-1Sc-0.3Zr) alloy powder on the FSW of AA2024 and AA6351 alloys was investigated. The experimentation was carried out at different speeds of 800, 1200, and 1600 rpm while maintaining a welding speed of 35 mm/min and an axial load of 3 kN. The master alloy powder was added to the base materials prior to welding, and the resulting welds were characterized using optical microscopy, scanning electron microscopy, hardness testing, tensile testing, and corrosion testing. At 800 rpm, the tensile strength increased from 200.7 MPa without powder to 241.8 MPa with powder and hardness values were notably higher in samples with powder, such as increasing from 98.3 HV without powder to 115.33 HV with powder at 1200 rpm. The addition of the Scandium enriched powder significantly improved the tensile strength, hardness, and corrosion resistance of the welds compared to welds produced without the use of this powder. The findings of this study suggest that incorporating Scandium enriched powder into the FSW process can effectively enhance the mechanical and corrosion properties of AA2024 and AA6351 alloy welds, thereby improving the overall performance of the welding process.

Keywords

• fsw performance
• scandium enriched powder
• welding speed
• axial load
• mechanical properties
• weld characterization