Observations of G-P Zone Reversion in Al-Zn-Mg Alloys by Small-Angle X-Ray Scattering and Transmission Electron Microscopy
A study of the reversion process in Al-Zn-Mg alloys has been made using small-angle X-ray scattering and transmission electron microscopy techniques. The rate and mode of Guinier-Preston zone dissolutions was investigated as a function of magnesium content, prior zone radius, and reversion temperature. Results indicate that in this system the reversion process is characterized by the preferential dissolution of the smallest G-P zones present after cold aging with a corresponding decrease in the volume fraction of zones. The amount of reversion at a specific temperature is dependent on magnesium content, however, the rate of reversion is independent of magnesium content.
KeywordsIntegrate Intensity Transmission Electron Micrographs Magnesium Content Zone Diameter Small Zone
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