PNNL

Abstract

The corrosion of nickel metal in a high-temperature aqueous tungstate solution is described. The corrosion altered the solution's pH, which affected the equilibrium of the tungstate solution chemistry. These secondary effects of the corrosion process were observed with in situ infra red (IR) spectroscopy, demonstrating that important information on corrosion phenomena at the solid-fluid interface may be obtained from in situ spectroscopic studies of the fluid phase. Subsequent scanning electron microscopy (SEM) analysis of the corroded nickel metal and solid corrosion products support conclusions drawn form the solution chemistry measurements. The presented findings are of interest to researchers and engineers that use pure nickel bearing alloys as a material for high temperature, high pressure applications in aqueous solutions.