Effect of Cl- concentration on the corrosion mechanism for N80 tubing steel
This article used a high-temperature and high-pressure Hastelloy reactor to simulate the harsh corrosion environment.The effects of different Cl-concentrations(0,5 000,10 000,15 000 mg/L)on the corrosion mechanism of N80 tubing steel in the extraction fluid was studied.The corrosion rate,corrosion morphology and corrosion film structure of N80 tubing steel was analyzed using a combination of macroscopic and microscopic means.The variability of corrosion in different Cl-content environments was clarified.The results showed that the corrosion rate rose significantly with the elevation of Cl-concentration,and the pits on the surface of the corrosion products gradually increased.The large amount of Cl-enrichment destroyed the originally dense corrosion film,exposing N80 tubing steel to the corrosion solution.The presence of trace O2 made the concentration difference battery occur,accelerating the corrosion process.
Cl-concentrationN80 tubing steelcorrosion behaviorcorrosion film