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Metallic nanostructures are an important target of studies, given their potential of application in technological devices, be it as means of basic research, or implementations in engineering, medicine, etc. Therefore much research in condensed matter is spent in developing and aprimorating eletronical and mechanical components at the nanoscale, employing either experiments or numerical simulations. In this context, an important class of structures are those presenting the shape memory effect (SME). The SME consists in a phase transition phenomenon in certain solids, stimulated mainly by temperature changes, which causes the structures to naturally return to a form they had before a mechanical distortion, characterized by changes on the solid’s crystalline lattices. Here, we focus on the NiTi metallic alloy, which presents the SME, and seek to study its phase transitions through molecular dynamics simulations, under the Tight-Binding second moment approximation (TB-SMA) formalism. We also seek to find out the formation of nanowires on such materials, also through molecular dynamics, on a varied range of temperatures. We present results on the phase transitions parting from two initial states, which are the B2 and B19 phases, which are the main transitions involved in SME. Also present is the growth of nanowires at different crystallographic directions and temperature conditions, regarding the phase transitions which happen during the formation of a nanowire as well.