The SCC (stress corrosion cracking) susceptibility of steel l6Mn in nitratesolution was studied. The results showed that applied potential polarization would accelerate(anodic polarization) or retard (cathodic polariz...The SCC (stress corrosion cracking) susceptibility of steel l6Mn in nitratesolution was studied. The results showed that applied potential polarization would accelerate(anodic polarization) or retard (cathodic polarization) the SCC process. The study on phaseelectrochemistry revealed that there was significant difference in electrochemical performancebetween ferrite and pearlite of steel 16Mn. Pearlite preferentially corroded under the action ofgalvanic cell. The observation on time and in situ showed that corrosion started first at the phaseboundary between ferrite and pearlite, and the pearlite gradually corroded until disappeared, andthen corrosion crossed the phase boundary extending into the ferrite phase. According to this, ananodic dissolution mechanism of SCC was proposed, on which pre-existing sting active path and phaseelectrochemistry (PEAP-PEC) jointly came into action (SCC mechanism of PEAP-PEC).展开更多
The passive film-induced stress and the susceptibility to SCC of 7050 aluminum alloy in 3.5%sodium chloride solution at various pH values were investigated by slow strain rate testing（SSRT） and flowing stress differ...The passive film-induced stress and the susceptibility to SCC of 7050 aluminum alloy in 3.5%sodium chloride solution at various pH values were investigated by slow strain rate testing（SSRT） and flowing stress differential method.The results showed that the passive film-induced stress and the susceptibility to SCC decreased with increasing pH values when pH≤7,while they increased with increasing pH values when pH7.However,the corrosion type was interpreted as exfoliation corrosion when pH=l and 14,and there was no film formed on the surface of the specimens.The whole variation plots of film-induced stress and the SCC susceptibility with pH values were both presented as a valley shape.The symbol and amount of the film-induced stress were related to the compositions of the passive film,which were analyzed using X-ray photoelectron spectroscopy（XPS）.展开更多
The effect of hydrogen on the dezincification layer-induced stress and the susceptibility to SCC was investigated. Experimental results showed that the dezincification layer-induced stress increased with increasing hy...The effect of hydrogen on the dezincification layer-induced stress and the susceptibility to SCC was investigated. Experimental results showed that the dezincification layer-induced stress increased with increasing hydrogen concentration, and 3x10-6 hydrogen could increase the susceptibility to SCC of brass in ammonia solution by 10%.展开更多
基金This work was supported by the National Natural Science Foundation of China (No. 5880009) and the Beijing Natural Science Foun-
文摘The SCC (stress corrosion cracking) susceptibility of steel l6Mn in nitratesolution was studied. The results showed that applied potential polarization would accelerate(anodic polarization) or retard (cathodic polarization) the SCC process. The study on phaseelectrochemistry revealed that there was significant difference in electrochemical performancebetween ferrite and pearlite of steel 16Mn. Pearlite preferentially corroded under the action ofgalvanic cell. The observation on time and in situ showed that corrosion started first at the phaseboundary between ferrite and pearlite, and the pearlite gradually corroded until disappeared, andthen corrosion crossed the phase boundary extending into the ferrite phase. According to this, ananodic dissolution mechanism of SCC was proposed, on which pre-existing sting active path and phaseelectrochemistry (PEAP-PEC) jointly came into action (SCC mechanism of PEAP-PEC).
基金Funded by the National Natural Science Foundation of China(No.51371039)
文摘The passive film-induced stress and the susceptibility to SCC of 7050 aluminum alloy in 3.5%sodium chloride solution at various pH values were investigated by slow strain rate testing（SSRT） and flowing stress differential method.The results showed that the passive film-induced stress and the susceptibility to SCC decreased with increasing pH values when pH≤7,while they increased with increasing pH values when pH7.However,the corrosion type was interpreted as exfoliation corrosion when pH=l and 14,and there was no film formed on the surface of the specimens.The whole variation plots of film-induced stress and the SCC susceptibility with pH values were both presented as a valley shape.The symbol and amount of the film-induced stress were related to the compositions of the passive film,which were analyzed using X-ray photoelectron spectroscopy（XPS）.
基金This project was supported by the Special Fund for the Major State Basic Research Project(G19990650)the NSFC(No.50071010)
文摘The effect of hydrogen on the dezincification layer-induced stress and the susceptibility to SCC was investigated. Experimental results showed that the dezincification layer-induced stress increased with increasing hydrogen concentration, and 3x10-6 hydrogen could increase the susceptibility to SCC of brass in ammonia solution by 10%.
