Fabrication of bulk nanostructure Al7075 alloy by mechanical alloying and hot pressing

In this study, production of bulk nanostructure Al7075 alloy by mechanical alloying and hot pressing was investigated. The elemental powders including Al, Zn, Mg and Cu were mixed and alloyed by high energy planetary ball mill and then hot pressed (HP) in an uniaxial die. The as-milled and hot pressed samples were characterized by X ray diffraction (XRD). In addition the hardness measurement was performed using the Vickers scale. The results showed that after 15h of milling Zn, Mg and Cu atoms dissolved in Al and a supersaturated solid solution formed. Hot pressing of 15h milled powders at 500 C under 400Mpa led to fully dense bulk nanostructure Al7075. The consolidated sample had a hardness value of about 165Hv and was stable up to 500C. The response to aging of this alloy demonstrated that the maximum hardness value (240Hv) was achieved in 30min.

کلیدواژه ها:

Mechanical alloying ، hot pressing ، Al7075 ، nanostructure