Microstructure, texture and mechanical properties of 6061 aluminum laser beam welded joints

Journal Article · Thu Mar 15 04:00:00 EDT 2018 · Materials Characterization

DOI:https://doi.org/10.1016/J.MATCHAR.2018.01.030· OSTI ID:22804928

Chu, Qiaoling ^[1]; Bai, Ruixiang ^[2]; Jian, Haigen ^[3]; Lei, Zhenkun ^[2]; Hu, Ning ^[4]; Yan, Cheng ^[5]

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1. College of Materials Science and Engineering, Xi’an University of Technology, Xi’an, 710048 (China)
2. State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian 116023 (China)
3. Hunan University of Technology, Zhuzhou 412007 (China)
4. College of Aerospace Engineering, Chongqing University, Chongqing 400044 (China)
5. School of Chemistry, Physics and Mechanical Engineering, Science and Engineering Faculty, Queensland University of Technology (QUT), Brisbane, QLD, 4001 (Australia)

Highlights: • Strong cube texture ({001}<100>) is observed in columnar dendrites. • The ratio of equiaxed dendrites shows proportional relationship with the strength. • The relations between process-microstructure-property are accurately established. - Abstract: In the present study, laser beam welding was carried out with 6061 Al alloy plate to study the microstructural evolution under various welding heat input (ηP/v = 30 J/mm, 38 J/mm, 46 J/mm, and 58 J/mm). The width of the weld metals increased continuously with the heat input values. Quantitatively correlation of the microstructure distribution with welding parameters was developed based on the EBSD results. The weld metals mainly consisted of coarse columnar dendrites and equiaxed dendrites. The ratio of equiaxed dendrites which were controlled by constitutional supercooling and heterogeneous nuclei showed directly proportional relationship with the weld strength. Strong cube texture ({001}<100>) was observed in columnar dendrites, which showed harmful effect on the weld strength. Slight softening in heat affected zone due to recrystallization was identified by nanoindentation tests. All specimens failed in weld metal and the fracture surfaces showed the characteristics of ductile fracture.

• OSTI ID: 22804928
• Journal Information: Materials Characterization, Journal Name: Materials Characterization Vol. 137; ISSN 1044-5803; ISSN MACHEX
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
BACKSCATTERING
DENDRITES
DISTRIBUTION
ELECTRON DIFFRACTION
HEAT AFFECTED ZONE
LASER WELDING
MICROSTRUCTURE
RECRYSTALLIZATION
SUPERCOOLING
SURFACES
WELDED JOINTS