Abstract
The automatic tungsten-inert gas welding (ATIGW) of AZ31 Mg alloys was performed using a six-axis robot. The evolution of the microstructure and texture of the AZ31 auto-welded joints was studied by optical microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and electron backscatter diffraction. The ATIGW process resulted in coarse recrystallized grains in the heat affected zone (HAZ) and epitaxial growth of columnar grains in the fusion zone (FZ). Substantial changes of texture between the base material (BM) and the FZ were detected. The {0002} basal plane in the BM was largely parallel to the sheet rolling plane, whereas the c-axis of the crystal lattice in the FZ inclined approximately 25° with respect to the welding direction. The maximum pole density increased from 9.45 in the BM to 12.9 in the FZ. The microhardness distribution, tensile properties, and fracture features of the AZ31 auto-welded joints were also investigated.
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Acknowledgements
This work is supported by the National Key Research and Development Plan of China (Grant Nos. 2016YFB0701200 and 2016YFB0301105), the Natural Science Foundation of Shandong Province, China (Grant Nos. ZR2015EQ019, BS2015CL016, and ZR2015YL007), and the Youth Foundation of Shandong Academy of Sciences, China (Grant No. 2016QN015).
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Liu, Ht., Zhou, Jx., Zhao, Dq. et al. Characteristics of AZ31 Mg alloy joint using automatic TIG welding. Int J Miner Metall Mater 24, 102–108 (2017). https://doi.org/10.1007/s12613-017-1383-8
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DOI: https://doi.org/10.1007/s12613-017-1383-8