The microstructural evolution of a pre-alloyed AZ91 magnesium alloy powder through high-energy milling and subsequent isothermal annealing Articles uri icon

publication date

  • May 2013

start page

  • 182

end page

  • 185

volume

  • 98

International Standard Serial Number (ISSN)

  • 0167-577X

Electronic International Standard Serial Number (EISSN)

  • 1873-4979

abstract

  • This study analyzed the effect of high-energy milling (HEM) and subsequent isothermal annealing on the microstructural characteristics of a pre-alloyed AZ91 Mg alloy powder. To this end, the mentioned powder was milled for 14 h using a horizontal attritor. Then, the mechanically milled powder was isothermally annealed at temperatures ranging from 200 degrees C to 500 degrees C for I h up to 4 h in an Ar atmosphere. HEM caused the beta-Mg17Al12 phase present in the microstructure of AZ91 powder particles to dissolve into their alpha-Mg solid solution matrix. In addition, the crystallite size of the alpha-Mg phase decreased to 25 nm through HEM. In contrast to the annealing time, the temperature of isothermal annealing had a significant effect on the microstructural features of the mechanically milled AZ91 powder.

keywords

  • az91 magnesium alloy; pre-alloyed powder; high-energy milling; isothermal annealing; microstructural evolution