Acta Metallurgica Sinica (English Letters) ›› 2020, Vol. 33 ›› Issue (1): 172-182.DOI: 10.1007/s40195-019-00966-4

Special Issue: 2019年铝合金专辑

• Original Paper • Previous Articles    

Microstructure and Corrosion Behavior of Friction Stir Welded Al Alloy Coated by In Situ Shot-Peening-Assisted Cold Spray

Hua Zhang1,3(), Chang-Yu Zhao1, Qi-Long Guo1, Rui-Sheng Yang2, Li-Yuan Liu2, San-Bao Lin3   

  1. 1 School of Mechanical Engineering, Beijing Institute of Petrochemical Technology, Beijing 102617, China
    2 Beijing Institute of Astronautical Systems and Engineering, Beijing 100076, China
    3 State Key Laboratory of Advanced Welding and Joining, Harbin Institute of Technology, Harbin 150001, China
  • Received:2019-03-14 Revised:2019-04-23 Online:2020-01-10 Published:2020-02-20
  • Contact: Zhang Hua

Abstract:

To improve the corrosion resistance of friction stir welded (FSW) joints, in situ shot-peening-assisted cold spray coating was applied to the surface of FSW joints. The microstructure and corrosion behavior of the coatings were investigated. The results showed that a dense coating was obtained by cold spraying technology. Moreover, the use of in situ shot-peening-assisted technology significantly reduced the porosity of the coating, which has a positive impact on the microstructure and the mechanical performance. Exfoliation corrosion tests showed that the coating affected positively on the corrosion resistance. On the coated surface, the craters caused by shot-peening particles were corroded in the form of exfoliation corrosion, while the exposed particles were corroded in the form of intercrystalline corrosion. This work provides a new approach to the corrosion protection of FSW joints.

Key words: Aluminum alloy coating, Cold spray, Friction stir welding, In situ shot-peening, Intergranular corrosion