High corrosion resistance of alloys is essential for their structural applications;however,most alloys suffer from degradation of their corrosion resistance with the increasing acidity of their surround-ings.Nonethele...High corrosion resistance of alloys is essential for their structural applications;however,most alloys suffer from degradation of their corrosion resistance with the increasing acidity of their surround-ings.Nonetheless,we developed a series of medium-entropy alloys(MEAs)in this work,which ex-hibit high strength,superior fracture toughness and ultra-high corrosion resistance,outperforming the variety of corrosion resistant alloys hitherto reported.Most interestingly,our MEAs exhibit an unusual anti-corrosion behavior and their corrosion resistance increases with acidity in Cl−containing solutions.Through extensive thermodynamic calculations,density functional theory(DFT)simulations and experi-ments,we reveal that the unusual anti-corrosion behavior of our MEAs can be attributed to their surface chemical complexity,which facilitates the physio-chemical-absorption of H_(2)O and O_(2)and thus the rapid formation of metastable medium entropy passive films that contain the lowest amount of defects,as compared to the passive films on conventional alloys reported in the literature.展开更多
In this work,we demonstrate that the corrosion resistance of the FeCrNiCoNb_(0.5) eutectic high entropy alloy(EHEA)can be tuned by controlling the size of its eutectic structure.Through microstructure refinement,the E...In this work,we demonstrate that the corrosion resistance of the FeCrNiCoNb_(0.5) eutectic high entropy alloy(EHEA)can be tuned by controlling the size of its eutectic structure.Through microstructure refinement,the EHEA exhibits a superb corrosion resistance in 1 M NaCl in terms of a very low corrosion current density and an ultra-high transpassviation potential,which outperforms a variety of other HEAs and conventional metals and alloys.At the fundamental level,the microstructure refinement results in a rapid formation of a thick and compact passive film with less Cl-adsorption on the EHEA,which results in significant enhancement in its corrosion resistance.The outcome of our research provides important insights into the design of corrosion resistant chemically complex alloys.展开更多
基金Y.Yang was supported by Research Grant Council(RGC),Hong Kong Government,through General Research Fund(RGC)(Nos.CityU11213118,CityU11200719 and CityU11209317).
文摘High corrosion resistance of alloys is essential for their structural applications;however,most alloys suffer from degradation of their corrosion resistance with the increasing acidity of their surround-ings.Nonetheless,we developed a series of medium-entropy alloys(MEAs)in this work,which ex-hibit high strength,superior fracture toughness and ultra-high corrosion resistance,outperforming the variety of corrosion resistant alloys hitherto reported.Most interestingly,our MEAs exhibit an unusual anti-corrosion behavior and their corrosion resistance increases with acidity in Cl−containing solutions.Through extensive thermodynamic calculations,density functional theory(DFT)simulations and experi-ments,we reveal that the unusual anti-corrosion behavior of our MEAs can be attributed to their surface chemical complexity,which facilitates the physio-chemical-absorption of H_(2)O and O_(2)and thus the rapid formation of metastable medium entropy passive films that contain the lowest amount of defects,as compared to the passive films on conventional alloys reported in the literature.
基金supported by the Research Grant Council(RGC),Hong Kong Government,through the General Research Fund(GRF)with the grant number City U11213118 and City U11209317。
文摘In this work,we demonstrate that the corrosion resistance of the FeCrNiCoNb_(0.5) eutectic high entropy alloy(EHEA)can be tuned by controlling the size of its eutectic structure.Through microstructure refinement,the EHEA exhibits a superb corrosion resistance in 1 M NaCl in terms of a very low corrosion current density and an ultra-high transpassviation potential,which outperforms a variety of other HEAs and conventional metals and alloys.At the fundamental level,the microstructure refinement results in a rapid formation of a thick and compact passive film with less Cl-adsorption on the EHEA,which results in significant enhancement in its corrosion resistance.The outcome of our research provides important insights into the design of corrosion resistant chemically complex alloys.
