Fiber Laser Welding–Brazing Characteristics of Dissimilar Metals AZ31B Mg Alloys to Copper with Mg-Based Filler

Journal Article · Thu Mar 15 04:00:00 EDT 2018 · Journal of Materials Engineering and Performance

DOI:https://doi.org/10.1007/S11665-018-3166-4· OSTI ID:22858053

Zhao, Xiaoye; Tan, Caiwang ^[1]; Meng, Shenghao; Chen, Bo ^[2]; Song, Xiaoguo; Li, Liqun; Feng, Jicai ^[1]

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1. Harbin Institute of Technology, State Key Laboratory of Advanced Welding and Joining (China)
2. Harbin Institute of Technology at Weihai, Shandong Provincial Key Laboratory of Special Welding Technology (China)

Fiber laser welding–brazing of 1-mm-thick AZ31B Mg alloys to 1.5-mm-thick copper (T2) with Mg-based filler was performed in a lap configuration. The weld appearance, interfacial microstructure and mechanical properties were investigated with different heat inputs. The results indicated that processing windows for optimizing appropriate welding parameters were relatively narrow in this case. Visually acceptable joints with certain strength were achieved at appropriate welding parameters. The maximum tensile-shear fracture load of laser-welded-brazed Mg/Cu joint could reach 1730 N at the laser power of 1200 W, representing 64.1% joint efficiency relative to AZ31Mg base metal. The eutectic structure (α-Mg + Mg{sub 2}Cu) and Mg-Cu intermetallic compound was observed at the Mg/Cu interface, and Mg-Al-Cu ternary intermetallic compound were identified between intermetallics and eutectic structure at high heat input. All the joints fractured at the Mg-Cu interface. However, the fracture mode was found to differ. For laser power of 1200 W, the surface was characterized by tearing edge, while that with poor joint strength was almost dominated by smooth surface or flat tear pattern.

• OSTI ID: 22858053
• Journal Information: Journal of Materials Engineering and Performance, Journal Name: Journal of Materials Engineering and Performance Journal Issue: 3 Vol. 27; ISSN 1059-9495; ISSN JMEPEG
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BRAZING
COPPER
EFFICIENCY
EUTECTICS
FIBERS
FILLERS
FRACTURES
INTERFACES
INTERMETALLIC COMPOUNDS
LASER WELDING
MAGNESIUM ALLOY-AZ31B
MECHANICAL PROPERTIES
MICROSTRUCTURE
PROCESSING
WELDED JOINTS