Through the experiment of natural seawater exposure corrosion, the antifouling properties of the plate specimens of 90Cu 10Ni alloy were studied, which were processed by different deformations, annealing treatments an...Through the experiment of natural seawater exposure corrosion, the antifouling properties of the plate specimens of 90Cu 10Ni alloy were studied, which were processed by different deformations, annealing treatments and surface treatments. The results indicate that after exposure corrosion for half a year, the antifouling properties of the specimens are quite different. The specimens processed by suitable deformations, annealing treatment at 650?℃ and pretreatment of surface film possess both good corrosion resistance and antifouling properties. However, the specimens processed by different deformations and annealing treatment at 450?℃ possess lower corrosion resistance, although they are also treated by the pretreatment of surface film; their antifouling properties change with different deformations. The relationships among the corrosion morphology and microstructure with the antifouling property of 90Cu 10Ni alloy are observed under the scanning electron microscopy (SEM).展开更多
Seawater pumped storage systems have bright prospect for energy storage in the coming years.The operational conditions of seawater pumped storage system are complex and harsh,where metal materials suff er from severe ...Seawater pumped storage systems have bright prospect for energy storage in the coming years.The operational conditions of seawater pumped storage system are complex and harsh,where metal materials suff er from severe general and local corrosion.The corrosion behavior of Q235B carbon steel in simulated seawater pumped storage system under operational conditions was studied by potentiodynamic polarization,cyclic potentiodynamic polarization,and scanning electron microscope(SEM).The results confi rm that the working pressure aff ected the corrosion resistance of Q235B carbon steel during the whole immersion period.The pressure promoted the electrochemical reaction of corrosion process and the corrosion rate increased with pressure at the initial immersion period.However,the stable rust layer formed after longtime immersion at diff erent pressures increased the corrosion resistance of carbon steel,and decreased the corrosion degree of carbon steel.Meanwhile,the working pressure aff ected the pitting corrosion behavior of Q235B carbon steel during the whole immersion period.The pitting corrosion potential was more negative and the tendency of pitting corrosion was higher at 4 MPa during the whole immersion period.However,pressure also accelerated the formation rate of protective rust layer on the steel surface.Q235B carbon steel has higher susceptibility to pitting corrosion at 4 MPa in the static seawater.展开更多
Electrochemical studies of the effect of hydrodynamic conditions on corrosion inhibition of Cu-Ni (90/10) alloy in synthetic seawater and sulphide containing synthetic seawater by 1,2,3-benzotriazole (BTAH) are pr...Electrochemical studies of the effect of hydrodynamic conditions on corrosion inhibition of Cu-Ni (90/10) alloy in synthetic seawater and sulphide containing synthetic seawater by 1,2,3-benzotriazole (BTAH) are presented. Impedance, potentiodynamic polarization and cyclic voltammetric (CV) studies are employed in the present investigation. The studies are carried out by using Cu-Ni (90/10) alloy rotating disc electrode at different rotation speeds and at different immersion periods. Reynolds numbers at each rotation speed infer that the flow of seawater is laminar. With increasing rotation speed of the electrode immersed in seawater without sulphide and BTAH, both the charge transfer resistance (Rot) and film resistance (Rf^lm) are increased. However, in the presence of sulphide ions and without BTAH, both the Rot and Rf,m are found to decrease with increasing rotation speed at identical immersion periods. Interestingly, when BTAH is added to seawater or seawater containing sulphide, both the Rot and Rf,m are increased to such a great extent that an inhibition efficiency of 99.99% is obtained. In the presence of BTAH, the phase angle Bode plots are more broadened and the maximum values of phase angle are increased to a value close to 90~ as the rotation speed is increased. The BTAH film is highly protective even under hydrodynamic condition also. Potentiodynamic polarization studies infer that BTAH functions as a mixed inhibitor under hydrodynamic conditions also. CV studies reveal that the protective BTAH film is stable even at anodic potentials of +850 mV vs Ag/AgCI.展开更多
文摘Through the experiment of natural seawater exposure corrosion, the antifouling properties of the plate specimens of 90Cu 10Ni alloy were studied, which were processed by different deformations, annealing treatments and surface treatments. The results indicate that after exposure corrosion for half a year, the antifouling properties of the specimens are quite different. The specimens processed by suitable deformations, annealing treatment at 650?℃ and pretreatment of surface film possess both good corrosion resistance and antifouling properties. However, the specimens processed by different deformations and annealing treatment at 450?℃ possess lower corrosion resistance, although they are also treated by the pretreatment of surface film; their antifouling properties change with different deformations. The relationships among the corrosion morphology and microstructure with the antifouling property of 90Cu 10Ni alloy are observed under the scanning electron microscopy (SEM).
基金Supported by the National Key R&D Program of China(Nos.2017YFB0903700,2017YFB0903702)。
文摘Seawater pumped storage systems have bright prospect for energy storage in the coming years.The operational conditions of seawater pumped storage system are complex and harsh,where metal materials suff er from severe general and local corrosion.The corrosion behavior of Q235B carbon steel in simulated seawater pumped storage system under operational conditions was studied by potentiodynamic polarization,cyclic potentiodynamic polarization,and scanning electron microscope(SEM).The results confi rm that the working pressure aff ected the corrosion resistance of Q235B carbon steel during the whole immersion period.The pressure promoted the electrochemical reaction of corrosion process and the corrosion rate increased with pressure at the initial immersion period.However,the stable rust layer formed after longtime immersion at diff erent pressures increased the corrosion resistance of carbon steel,and decreased the corrosion degree of carbon steel.Meanwhile,the working pressure aff ected the pitting corrosion behavior of Q235B carbon steel during the whole immersion period.The pitting corrosion potential was more negative and the tendency of pitting corrosion was higher at 4 MPa during the whole immersion period.However,pressure also accelerated the formation rate of protective rust layer on the steel surface.Q235B carbon steel has higher susceptibility to pitting corrosion at 4 MPa in the static seawater.
基金Naval Research Board(NRB), Govt.of IndiaRajiv Gandhi National Fellowship(RGNF),UGC,Govt.of India
文摘Electrochemical studies of the effect of hydrodynamic conditions on corrosion inhibition of Cu-Ni (90/10) alloy in synthetic seawater and sulphide containing synthetic seawater by 1,2,3-benzotriazole (BTAH) are presented. Impedance, potentiodynamic polarization and cyclic voltammetric (CV) studies are employed in the present investigation. The studies are carried out by using Cu-Ni (90/10) alloy rotating disc electrode at different rotation speeds and at different immersion periods. Reynolds numbers at each rotation speed infer that the flow of seawater is laminar. With increasing rotation speed of the electrode immersed in seawater without sulphide and BTAH, both the charge transfer resistance (Rot) and film resistance (Rf^lm) are increased. However, in the presence of sulphide ions and without BTAH, both the Rot and Rf,m are found to decrease with increasing rotation speed at identical immersion periods. Interestingly, when BTAH is added to seawater or seawater containing sulphide, both the Rot and Rf,m are increased to such a great extent that an inhibition efficiency of 99.99% is obtained. In the presence of BTAH, the phase angle Bode plots are more broadened and the maximum values of phase angle are increased to a value close to 90~ as the rotation speed is increased. The BTAH film is highly protective even under hydrodynamic condition also. Potentiodynamic polarization studies infer that BTAH functions as a mixed inhibitor under hydrodynamic conditions also. CV studies reveal that the protective BTAH film is stable even at anodic potentials of +850 mV vs Ag/AgCI.