In Situ Fabrication and Characterization of (NiCr)Al-Al2O3 Nanocomposite by Mechanical Alloying
|Periodical||Journal of Nano Research (Volume 16)|
|Main Theme||Journal of Nano Research Vol. 16|
|Citation||Amir Reza Shirani-Bidabadi et al., 2012, Journal of Nano Research, 16, 21|
|Online since||January, 2012|
|Authors||Amir Reza Shirani-Bidabadi, Ali Shokuhfar, Mohammad Hossein Enayati, Mazda Biglari|
|Keywords||(NiCr)Al-Al2O3, Intermetallic Matrix Composite, Mechanical Alloying, Nanocomposite|
In this research, the formation mechanisms of a (NiCr)Al-Al2O3 nanocomposite were investigated. The structural changes of powder particles during mechanical alloying were studied by X-ray difractometry (XRD) and the morphology and cross sectional microstructure of powder particles were characterized by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The methodology involved mechanical alloying of NiO, Cr, and Al with molar ratios of 3:3:8. During mechanical alloying, NiO was first quickly reduced by aluminum atoms to produce NiAl nanocrystalline and Al2O3. Subsequently, and when a longer milling time was applied, chromium atoms diffused into the NiAl lattice. The heat treatment of this structure led to the formation of the (NiCr)Al intermetallic compound as well as Al2O3 with crystalline sizes of 23 nm and 58 nm, respectively.