Hits:

Indexed by:期刊论文

Date of Publication:2012-07-01

Journal:MATERIALS CHARACTERIZATION

Included Journals:SCIE、EI

Volume:69

Page Number:84-89

ISSN No.:1044-5803

Key Words:Welding; Intermetallics; Microstructure; Tensile strength

Abstract:Based on the idea of alloying welding seam, Gas tungsten arc welding method with pure Zn filler metal was chosen to join Mg alloy and Al alloy. The microstructures, phases, element distribution and fracture morphology of welding seams were examined. The results indicate that there was a transitional zone in the width of 80-100 mu m between the Mg alloy substrate and fusion zone. The fusion zone was mainly composed of MgZn2, Zn-based solid solution and Al-based solid solution. The welding seam presented distinct morphology in different location owning to the quite high cooling rate of the molten pool. The addition of Zn metal could prevent the formation of Mg-Al intermetallics and form the alloyed welding seam during welding. Therefore, the tensile strengths of joints have been significantly improved compared with those of gas tungsten arc welded joints without Zn metal added. (C) 2012 Elsevier Inc. All rights reserved.