Galfenol is a new magnetostrictive material with potential applications in sensors for acoustic waves. The purpose of the present investigation is to study the properties of galfenol nanowires of nanometer range diameter relevant to sensing of acoustic waves using the phenomenon of magnetostriction. In this endeavor we study first the basic energetics for this material. Then we investigate the macro-scale behaviour for galfenol using the theory of "Large body limits in Ferro-magnetism" of Desimone [DS93]. Subsequently we look at the existence and stability of single domain states in galfenol nanowires. The theoretical predictions are then verified by numerical methods.