The galvanic effect of high-strength weathering steel welded joints and its influence on corrosion resistance

ABSTRACT

The influence of the galvanic effects on the welded joints of A710 high-strength weathering steel with two different weld metals (80Ni1-H4 and WER70) under a simulated marine atmospheric environment was investigated by employing Scanning Kelvin Probe (SKP), galvanic current measurements, cyclic wet/dry accelerated corrosion testing, Field-Emission Scanning Electron Microscopy (FE-SEM) and other approaches. The results indicate that the average galvanic currents for the HAZ-BM and HAZ-WM couples of the two welded joints initially decreased and then gradually stabilised, which is related to the formation of a stable rust layer. In addition, the WER70 welded joints presented a higher average corrosion rate than for the 80Ni1-H4 welded joints. The significant galvanic effect of the WER70 welded joints and the formation of a compact rust layer are the dominant effects during the initial and later corrosion stages, respectively.

KEYWORDS:

• A710 steel
• welded joints
• galvanic corrosion
• SKP

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by National Key R&D Program of China (No: 2017YFB0304801)   and   the National Natural Science Foundation of China (No: 51871172).