Graphene has emerged as the most popular subject area in the active research field since its discovery in 2004. The published documents illustrate the popularity of Graphene research and innovations, spontaneously increased from about 150 in 2004 to 21,500 in 2018. Graphene is relatively young but high-hope for markets. The cover photo of May 2019 issue describes the structure of a cylindrical Graphene to celebrate the 15th anniversary of it's discovery.
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
Adv. Mater. Lett., 2019, 10 (5), pp 361-365
Publication Date (Web): Jan 14, 2019
Copyright © 2019 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.