Electrochemical dissolution behavior of heat treated laser solid formed Inconel718

Microstructure characteristic and its effects on electrochemical dissolution behavior of horizontal plane (HP) and vertical plane (VP) in the laser solid formed (LSF) Inconel718 alloy after double aging (DA) heat treatment (DA-LSF Inconel718) were investigated. Compared to the as-deposited one, DA-LSF Inconel718 shows more phases and presents electrochemical anisotropy between HP and VP including the polarization curves, current efficiency curves and surface roughness. It is caused by different electrochemical dissolution processes on HP and VP and proved that surface energy has no obvious effect. Three models were proposed to illustrate electrochemical dissolution behavior, surface formation mechanism and electrochemical anisotropy, respectively.