Effects of Post-welded Heat Treated on the AZ31B Magnesium Alloy Joint Welded by Automatic TIG Welding

  • Hongtao Liu
  • Wenyi Cheng
  • Ruochao Wang
  • Jixue Zhou
  • Yanfei Chen
  • Jinwei Wang
  • Yuansheng Yang
Conference paper
Part of the Lecture Notes in Mechanical Engineering book series (LNME)


The automatic TIG welding on AZ31B alloys was carried out by the six-axis robot in the present work. After post-welded heat treatment (PWHT), the microstructure, precipitates, and mechanical properties of the AZ31B joints were investigated by using the optical microscope (OM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The experimental results reveal that after PWHT, the microstructure and mechanical properties of the AZ31B joints were both significantly improved. After PWHT, the grains of the AZ31B joint were still fine, whereas the number of the precipitates along with the grain boundaries was dramatically decreased. The ultimate tensile strength (UTS) and the elongation (EL) of the PWHT AZ31B joints were up to the 100 and 96.9% of the base metal (BM), respectively.


Automatic TIG welding AZ31B magnesium alloy Post-welded heat treated (PWHT) Microstructure β-Mg17Al12 precipitates Mechanical properties 



This work is supported by the National Key Research and Development plan of China (Grant No. 2017YFB0103904, 2016YFB0301105), the Shandong Province Key Research and Development Plan, China (Grant No. 2017CXGC0404, 2016ZDJS02A09), and the Youth Foundation of Shandong Academy of Sciences, China (Grant No. 2016QN015).


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Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  • Hongtao Liu
    • 1
  • Wenyi Cheng
    • 2
  • Ruochao Wang
    • 3
  • Jixue Zhou
    • 1
  • Yanfei Chen
    • 4
  • Jinwei Wang
    • 1
  • Yuansheng Yang
    • 5
  1. 1.Shandong Key Laboratory for High Strength Lightweight Metallic MaterialsAdvanced Materials Institute, Shandong Academy of SciencesJinanChina
  2. 2.Shandong Urban Construction Vocational CollegeJinanChina
  3. 3.Shandong Institute of Commerce and TechnologyJinanChina
  4. 4.Shandong Engineering Research Center for Lightweight Automobiles Magnesium Alloys, Advanced Materials Institute, Shandong Academy of SciencesJinanChina
  5. 5.Institute of Metal Research, Chinese Academy of SciencesShenyangChina

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