Influence of FSW and MIG on the Mechanical Properties of Al-Mg-Mn Alloy with Minor Additions of 0.4% Sc And 0.1% Zr

Abstract

The present work focuses on the influence of solid-state welding, namely, friction stir welding (FSW) and arc welding, namely, metal inert gas welding (MIG), on the mechanical characteristics of new lightweight 5 mm thick Al-Mg-Mn alloy plates with the addition of 0.4% Sc and 0.1% Zr. The alloys were fabricated using aluminium with 10% magnesium, aluminium with 2% scandium, and aluminium with 5% zirconium master alloys in combination with the Al-Mg-Mn alloy- with the help of a stir casting melting technique. The hardness, tensile strength, 3-point bend strength, impact strength and microstructure of the rolled Al-Mg-Mn alloy plates with the addition of 0.4% Sc and 0.1% Zr were examined. Both the mechanical properties of the FSW and MIG weld joints were compared with those of the non-welded plates. The strength of the non-welded Al-Mg-Mn-Sc-Zr alloy plates was greater, than that of the FSW and MIG weld joints. However, the friction stir welded joints exhibited the improved mechanical properties in comparison with those the MIG welded joints due to more refined precipitation. Compared with the non-welded Al-Mg-Mn-Sc-Zr alloy plates, the friction stir welded joint exhibited a 91.6% joint efficiency and a 63.8% metal inert gas welded joint.

Keywords

• al-mg-mn
• scandium
• zirconium
• solid state welding
• gas-metal arc welding
• mechanical behavior