Exploring the passivity and electrochemical behavior of Inconel alloy 625 in nitric acid solution could open up possibilities for potential applications,either in bulk form or as claddings.Hence,this research investig...Exploring the passivity and electrochemical behavior of Inconel alloy 625 in nitric acid solution could open up possibilities for potential applications,either in bulk form or as claddings.Hence,this research investigates corrosion behavior and passivity of Inconel alloy 625 in nitric acid solutions of varying concentrations(0.01–1.00 mol/L)using a range of analytical techniques,including potentiodynamic polarization testing,chronoamperometry measurement,Mott-Schottky(MS)analysis,X-ray diffraction(XRD)approaches,and point defect modeling(PDM).Results demonstrate that corrosion current density does not necessarily decrease with increasing electrolyte concentration(Please check it out).Additionally,the alloy exhibits higher passive film transpassive potentials in more concentrated solutions.Potentiostatic polarization tests reveal an increase in steady-state current densities attributed to the passive films formed in more concentrated solutions.Lower electrolyte concentrations lead to the formation of more intact bilayered passive films.In this context,the formation of passive films is elucidated by examining the generation and annihilation of point defects.The semiconducting behavior of passive layers is further examined through XRD patterns and electrochemical properties.According to PDM,the diffusivity of point defects within the passive films and their respective donor densities can be closely correlated.展开更多
Friction stir processing(FSP)was employed as a post-printing surface modification technique to enhance surface properties of arc-directed energy deposited 316 L austenitic stainless-steel parts.Corrosion properties an...Friction stir processing(FSP)was employed as a post-printing surface modification technique to enhance surface properties of arc-directed energy deposited 316 L austenitic stainless-steel parts.Corrosion properties and passivity of stir zone and base metal were investigated in 3.5 wt.%NaCl solution.Results reveal a gradual improvement in corrosion protection ability of formed passive film on the alloy's surface over time.Specifically,FSPed region exhibited superior passive behavior and uniform corrosion resistance compared to base metal.This improvement was attributed to a more homogeneous microstructure of stir zone,which hindered micro-galvanic coupling effect.However,it was observed that FSP-treatment did not effectively impede the propagation of pitting corrosion.展开更多
基金the generous support provided by the Natural Sciences and Engineering Research Council of Canada(NSERC)(RGPIN-2017–04368)the Canada Research Chair Program(CRC-2019–00017),Ocean Frontier Institute,and Dalhousie University in making this work possible
文摘Exploring the passivity and electrochemical behavior of Inconel alloy 625 in nitric acid solution could open up possibilities for potential applications,either in bulk form or as claddings.Hence,this research investigates corrosion behavior and passivity of Inconel alloy 625 in nitric acid solutions of varying concentrations(0.01–1.00 mol/L)using a range of analytical techniques,including potentiodynamic polarization testing,chronoamperometry measurement,Mott-Schottky(MS)analysis,X-ray diffraction(XRD)approaches,and point defect modeling(PDM).Results demonstrate that corrosion current density does not necessarily decrease with increasing electrolyte concentration(Please check it out).Additionally,the alloy exhibits higher passive film transpassive potentials in more concentrated solutions.Potentiostatic polarization tests reveal an increase in steady-state current densities attributed to the passive films formed in more concentrated solutions.Lower electrolyte concentrations lead to the formation of more intact bilayered passive films.In this context,the formation of passive films is elucidated by examining the generation and annihilation of point defects.The semiconducting behavior of passive layers is further examined through XRD patterns and electrochemical properties.According to PDM,the diffusivity of point defects within the passive films and their respective donor densities can be closely correlated.
基金the support provided by the Natural Sciences and Engineering Research Council of Canada(NSERC)[grant number RGPIN-2017–04368]the Canada Research Chair program[grant number CRC-2019–00017],Ocean Frontier Institute,and Dalhousie University in making this work possiblethe Herff College of Engineering at the University of Memphis for the financial support of the research through the HCOE-FRG program
文摘Friction stir processing(FSP)was employed as a post-printing surface modification technique to enhance surface properties of arc-directed energy deposited 316 L austenitic stainless-steel parts.Corrosion properties and passivity of stir zone and base metal were investigated in 3.5 wt.%NaCl solution.Results reveal a gradual improvement in corrosion protection ability of formed passive film on the alloy's surface over time.Specifically,FSPed region exhibited superior passive behavior and uniform corrosion resistance compared to base metal.This improvement was attributed to a more homogeneous microstructure of stir zone,which hindered micro-galvanic coupling effect.However,it was observed that FSP-treatment did not effectively impede the propagation of pitting corrosion.
