Hits:

Indexed by:期刊论文

Date of Publication:2009-11-01

Journal:JOURNAL OF MATERIALS SCIENCE

Included Journals:SCIE、EI、Scopus

Volume:44

Issue:21

Page Number:5725-5731

ISSN No.:0022-2461

Abstract:Lap joint of magnesium alloy AZ31B to mild steel Q235 with the addition of copper interlayer by hybrid laser-TIG welding technique was investigated. The microstructure, element distribution at interfaces, and intermediate phases of joints were examined by scanning electron microscopy (SEM), electron probe micro-analyzer (EPMA), and X-ray diffraction (XRD), respectively. The results showed that intermetallic compounds Mg(2)Cu with rod-like structure in the joint and equiaxed structure at interface were found, and the bonding between copper and steel was realized by mixing of copper and steel at upper margins of molten pool and a little solid solution of copper in iron at the bottom and side of molten pool. Besides, comparing with that without any interlayer, the wettability of molten magnesium alloy on steel was enhanced, which led to an intimate connection. In the end, the joining mechanism of magnesium-steel joints with copper interlayer was discussed.