Effect of minor Er and Zr on microstructure and mechanical properties of Al–Mg–Mn alloy (5083) welded joints

• Published in: Materials science & engineering. A, Structural materials : properties, microstructure and processing Vol. 561; pp. 226 - 231
• Main Authors: dongxia, Yang, xiaoyan, Li, dingyong, He, hui, Huang
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 20-01-2013; Elsevier
• Subjects: Al–Mg–Mn alloy; Applied sciences; Condensed matter: structure, mechanical and thermal properties; Elasticity, elastic constants; Elasticity. Plasticity; Erbium; Exact sciences and technology; Grain refinement; Hardness; Joining, thermal cutting: metallurgical aspects; Laser welding; Mechanical and acoustical properties of condensed matter; Mechanical properties and methods of testing. Rheology. Fracture mechanics. Tribology; Mechanical properties of solids; Metals. Metallurgy; Physics; Welding; Zirconium; Zirconium; Al–Mg–Mn alloy; Laser welding; Erbium; Grain refinement; Grain size; Strengthening; Ultimate strength method; Property composition relationship; Mechanical properties; Equiaxed structure; Al―Mg―Mn alloy; Microhardness; Tension test; Structure composition relationship; Tensile strength; Weld; Hardening; Welding metallurgy; Welded joint; Fine grain structure; Erbium addition; Yield strength; Property structure relationship; Microstructure
• ISSN: 0921-5093; 1873-4936
• DOI: 10.1016/j.msea.2012.11.002

Samples of Al–Mg–Mn and Al–Mg–Mn–Er–Zr alloys were welded using the method of laser welding. The influence of Er and Zr on microstructure, microhardness and mechanical properties of the Al–Mg–Mn alloy welded joints were investigated. It has been found that addition of Er and Zr refines the grain size in the fusion zone, due to the formation of primary Al3Zr and Al3Er. Fine equiaxed grains are dominated near the fusion boundary of the Al–Mg–Mn–Er–Zr alloy joint, which is contrary with the columnar crystal in the Al–Mg–Mn alloy joint. Microhardness of the center of the fusion zone rises from 74HV0.1 to 84HV0.1 owing to the grain refinement by Er and Zr. The tensile test result shows that the ultimate tensile strength and yield strength are improved by adding Er and Zr. The main reason for this is related to grain refining strengthening.