The effect of age-hardening on microstructure,hardness,and corrosion of an Al-5at.%V alloy,produced us-ing high-energy ball milling and subsequent cold compaction,has been investigated.The alloy exhibited a grain size...The effect of age-hardening on microstructure,hardness,and corrosion of an Al-5at.%V alloy,produced us-ing high-energy ball milling and subsequent cold compaction,has been investigated.The alloy exhibited a grain size below 100 nm and extremely high solid solubility of V in Al(3.1 at.%).The age-hardening was carried out at 150,200,and 250℃.The peak-aged condition of 150℃ demonstrated the highest hardness-transpired from grain refinement,precipitation,and solid solution hardening.The corrosion re-sistance of the Al-5at.%V alloy was studied as a function of aging conditions.The peak-aged condition retained the corrosion resistance while it deteriorated in the over-aged condition.Nonetheless,the cor-rosion resistance of the ball-milled Al alloys in all the aging conditions was superior to that of pure Al.The passive film structure and origin of corrosion were studied using scanning/transmission electron mi-croscopy(S/TEM).The high corrosion resistance of the alloy was attributed to the V enrichment at the film/metal interface and deposition of V on the cathodic phases,which suppresses the dissolution of Al within the pit and therefore promotes repassivation in the early stages of corrosion.展开更多
The corrosion behavior of Al-5 at.% Cr, A1-5 at.% Si, Al-5 at.% Mo and Al-5 at.% Ti produced via casting and Al-5 at.% Cr produced by high-energy ball milling and subsequent consolidation by cold pressing was studied ...The corrosion behavior of Al-5 at.% Cr, A1-5 at.% Si, Al-5 at.% Mo and Al-5 at.% Ti produced via casting and Al-5 at.% Cr produced by high-energy ball milling and subsequent consolidation by cold pressing was studied using potentiodynamic polarization and surface analysis following constant immersion tests. Alloys were characterized using a scanning electron microscope coupled with the energy-dispersive X-ray spectroscopy and X-ray diffraction analysis. Hardness, a representative of the strength, was also measured. The alloys produced by casting contained coarse intermetallics and therefore exhibited poor corrosion resistance. Al-5 at.% Cr alloy produced by high-energy ball milling exhibited a significantly improved corrosion resistance and hardness, which was attributed to the grain refinement to nanoscale and extended solid solubility of Cr in AL The study indicated that the high-energy ball milling was capable of producing Al alloys with improved corrosion behavior and hardness.展开更多
基金The authors would like to acknowledge the financial support received from the National Science Foundation(Nos.NSF-CMMI 1760204 and NSF-CMMI 2131440)under the direction of Dr.Alexis Lewis.This work was performed in part at the Analytical Instrumentation Facility(AIF)at North Carolina State University,supported by the State of North Carolina and the National Science Foundation(award number ECCS-2025064).The AIF is a member of the North Carolina Research Triangle Nanotechnology Network(RTNN),a site in the National Nanotechnology Coordinated Infras-tructure(NNCI).
文摘The effect of age-hardening on microstructure,hardness,and corrosion of an Al-5at.%V alloy,produced us-ing high-energy ball milling and subsequent cold compaction,has been investigated.The alloy exhibited a grain size below 100 nm and extremely high solid solubility of V in Al(3.1 at.%).The age-hardening was carried out at 150,200,and 250℃.The peak-aged condition of 150℃ demonstrated the highest hardness-transpired from grain refinement,precipitation,and solid solution hardening.The corrosion re-sistance of the Al-5at.%V alloy was studied as a function of aging conditions.The peak-aged condition retained the corrosion resistance while it deteriorated in the over-aged condition.Nonetheless,the cor-rosion resistance of the ball-milled Al alloys in all the aging conditions was superior to that of pure Al.The passive film structure and origin of corrosion were studied using scanning/transmission electron mi-croscopy(S/TEM).The high corrosion resistance of the alloy was attributed to the V enrichment at the film/metal interface and deposition of V on the cathodic phases,which suppresses the dissolution of Al within the pit and therefore promotes repassivation in the early stages of corrosion.
文摘The corrosion behavior of Al-5 at.% Cr, A1-5 at.% Si, Al-5 at.% Mo and Al-5 at.% Ti produced via casting and Al-5 at.% Cr produced by high-energy ball milling and subsequent consolidation by cold pressing was studied using potentiodynamic polarization and surface analysis following constant immersion tests. Alloys were characterized using a scanning electron microscope coupled with the energy-dispersive X-ray spectroscopy and X-ray diffraction analysis. Hardness, a representative of the strength, was also measured. The alloys produced by casting contained coarse intermetallics and therefore exhibited poor corrosion resistance. Al-5 at.% Cr alloy produced by high-energy ball milling exhibited a significantly improved corrosion resistance and hardness, which was attributed to the grain refinement to nanoscale and extended solid solubility of Cr in AL The study indicated that the high-energy ball milling was capable of producing Al alloys with improved corrosion behavior and hardness.