Abstract
In the present study, the tensile and fatigue properties of extruded 7075 Al alloys subjected to re-solution treatment and then T6, T73 and retrogression-reaging (RRA) tempers were reassessed based upon the microstructural analyses by means of electron backscattering diffraction (EBSD) and X-ray diffraction (XRD). The microstructural analyses indicated that fibrous grains having orientations close to <111> and <001> were preferentially aligned in the extrusion direction and that re-solution treatment increased the fraction of <111> grains. Further the as-received T6 specimens had very high dislocation density as well as fine subgrains, while the re-solution treatment decreased dislocation density considerably and increased grain size. These characteristics explained tensile properties well, by taking into account the effect of precipitates formed by tempers. On the other hand, fatigue strength decreased prominently in all of the specimens, as the relative humidity (RH) was increased from 25% to 85%. T73 and RRA treatments which improve the resistance to stress corrosion cracking (SCC) in static loading were not effective in the humidity-enhanced deterioration in fatigue strength.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
