Ghadimi, M.Shokuhfar, A.Rostami H.R.Ghaffari, M.2016-02-082016-02-0820120167577Xhttp://hdl.handle.net/11693/21382Nickel and Titanium elemental powders with a nominal composition Ni-50 at.%Ti were mechanical alloyed in a planetary high-energy ball mill in different milling conditions (5, 10, 20, 40 and 60 h). The investigation revealed that increasing milling time leads to a reduction in crystallite size, and after 60 h of milling, the Ti dissolved in Ni lattice and NiTi (B2) phase was obtained. With milling time, morphology of pre-alloyed powders changed from lamella to globular. Annealing of as-milled powders at 1173 K for 900 s led to formation of nanocrystalline NiTi (B19′), grain growth and release of internal strain. The results indicated that this technique is a powerful and high productive process for preparing NiTi intermetallic compound with nanocrystalline structure and appropriate morphology. © 2012 Elsevier B.V. All rights reserved.EnglishElectron microscopyIntermetallic alloys and compoundsNanocrystalline materialsPhase transformationShape memory materialsX-ray techniquesAs-milled powdersElemental powdersHigh energyIntermetallic alloys and compoundsInternal strainsMilling conditionsMilling timeNano-crystalline NiTiNano-crystalline structuresNanocrystallinesNominal compositionPre-alloyed powderProductive processShape-memory materialsStructural characterizationX-ray techniquesBall millsElectron microscopyGrain growthIntermetallicsMechanical alloyingMilling (machining)MorphologyNanocrystalline materialsPhase transitionsPowdersSoldering alloysTitaniumNanocrystalline powdersArticle10.1016/j.matlet.2012.04.098