Effects of interrupted ageing(T6I6) and asymmetric rolling on microstructures, mechanical properties, and intergranular corrosion(IGC) behaviors of Al-Mg-Si-Zn alloy were investigated. Results showed that the T6 alloy...Effects of interrupted ageing(T6I6) and asymmetric rolling on microstructures, mechanical properties, and intergranular corrosion(IGC) behaviors of Al-Mg-Si-Zn alloy were investigated. Results showed that the T6 alloy has the lowest strength and the worst IGC resistance, while the T6I6 alloy has higher strength and better IGC resistance.What’ s more, the alloy treated by pre-rolling deformation has higher strength and better IGC resistance;and the alloy treated by the pre-asymmetry rolling achieves the highest strength, the best IGC resistance and lower elongation. The mechanical properties depend on microstructures such as the grain size, texture, dislocation density and precipitation, the grain boundary misorientation and grain boundary microstructure are responsible for the IGC resistance.展开更多
The through-thickness corrosion inhomogeneity of 7050-T7451 Al alloy thick plate was studied using immersion tests, potentiodynamic polarization, electrochemical impedance spectroscopy(EIS), slow strain rate testing(S...The through-thickness corrosion inhomogeneity of 7050-T7451 Al alloy thick plate was studied using immersion tests, potentiodynamic polarization, electrochemical impedance spectroscopy(EIS), slow strain rate testing(SSRT) technique combined with optical microscopy(OM), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results show that the through-thickness corrosion resistance is ranked in the order of T/2>surface>T/4. And the 75 mm-thick 7050 alloy plate presents better corrosion resistance than the 35 mm-thick plate. The results are discussed in terms of the combined effect of recrystallization and cooling rate in quenching. Alloy with lower volume fraction of recrystallization and smaller grain aspect ratio displays better corrosion resistance. The lower corrosion resistance caused by the slower cooling rate results from the higher coverage rate of grain boundary precipitates and larger width of precipitate free zone.展开更多
基金Project(TC190H3ZV/2) supported by the National Building Project of Application Demonstration Platform on New Materials Products,China。
文摘Effects of interrupted ageing(T6I6) and asymmetric rolling on microstructures, mechanical properties, and intergranular corrosion(IGC) behaviors of Al-Mg-Si-Zn alloy were investigated. Results showed that the T6 alloy has the lowest strength and the worst IGC resistance, while the T6I6 alloy has higher strength and better IGC resistance.What’ s more, the alloy treated by pre-rolling deformation has higher strength and better IGC resistance;and the alloy treated by the pre-asymmetry rolling achieves the highest strength, the best IGC resistance and lower elongation. The mechanical properties depend on microstructures such as the grain size, texture, dislocation density and precipitation, the grain boundary misorientation and grain boundary microstructure are responsible for the IGC resistance.
基金Project(2012CB619503)supported by the National Basic Research Program of ChinaProject(2013AH100055)supported by the Foshan Civic Technological Innovation Foundation,China
文摘The through-thickness corrosion inhomogeneity of 7050-T7451 Al alloy thick plate was studied using immersion tests, potentiodynamic polarization, electrochemical impedance spectroscopy(EIS), slow strain rate testing(SSRT) technique combined with optical microscopy(OM), scanning electron microscopy(SEM) and transmission electron microscopy(TEM). The results show that the through-thickness corrosion resistance is ranked in the order of T/2>surface>T/4. And the 75 mm-thick 7050 alloy plate presents better corrosion resistance than the 35 mm-thick plate. The results are discussed in terms of the combined effect of recrystallization and cooling rate in quenching. Alloy with lower volume fraction of recrystallization and smaller grain aspect ratio displays better corrosion resistance. The lower corrosion resistance caused by the slower cooling rate results from the higher coverage rate of grain boundary precipitates and larger width of precipitate free zone.
