Effect of diamantane on the thermal stability of cryomilled aluminum alloy
Walid M. Hanna1*, Farghalli A. Mohamed2
1Materials Engineering Department, Military Technical College, Kobry‑Elkoba, Cairo, 11843, Egypt
2Department of Chemical Engineering and Materials Science, University of California, Irvine, CA92697, USA
Publication Date (Web): Jan 14, 2019
Copyright © 2018 VBRI Press
The thermal stability behavior of Al-5083 cryomilled nanocrystalline powders stabilized by diamantane nanoparticles was studied in comparison with the alloy without diamantane. Nanocrystalline Al 5083 powders were produced by mechanical milling in a liquid nitrogen medium. The results revealed that Al 5083 with diamantane showed higher thermal stability than the cryomilled alloy without diamantane in the temperature limit from 473 °K to 773 °K (0.56 to 0.91Tm) for various annealing times from 0.5 h to 48 h. In this regard, calculations showed that while the grain size was still in the nano scale in the presence of diamantane, it was in the ultrafine range (> 150 nm) in the absence of diamantane. The above finding was qualitatively explained in terms of Zener’s concept.
Cryomilling, Diamantane, grain boundaries, nanocrystalline materials, thermal stability.