Corrosion behavior and mechanism of laser additive manufactured Ni-based alloy in CO2 environment at different temperatures and pressures

This paper reports the effect of temperature and CO2 partial pressure on the corrosion behavior and mechanism of LAM Ni-based alloy in oilfield produced water. The passive current density and critical current density of LAM Ni-based alloy increased, while pitting potential and thickness of passive film decreased as the increase of temperature and CO2 partial pressure. Pitting corrosion was found at the interface between γ-Ni and inclusions, while the occluded cell corrosion (OCC) was formed by the deposited layer of CaCO3. The OCC worsened pitting corrosion was the main degradation mechanism of LAM Ni-based alloy. The findings provided theoretical guidance for understanding CO2 behavior and mechanism in LAM alloys.