Light materials have been studied thoroughly and used in components and parts in the automobile, naval and aerospace industries in the last decade. Their application makes possible: to reduce the mass, to increase the load capacity, increase of the speed and, and improvement in the mechanical properties when it is possible. Among those materials, the aluminium - magnesium alloys have special attention due, not only to the lightness of the material, but also to certain mechanical properties and reciclability. The addition of zirconium in the Al-Mg alloys make it less susceptible to fatigue corrosion crack and it aids in the control of the natural aging, that causes the loss of the ductility. However the solubility of the zirconium in the Al-Mg alloys is low, not exceeding 0,28% for alloys manufactured by conventional metallurgy; and the use of not conventional techniques (powder metallurgy) it can increase to 2,5 to 5 times the limit of normal solubility. Previous works show that the addition of 0,1% in weight in an Al-10Mg alloy, it also increases the mechanical properties, being pronounced the superplasticity in these alloys. The aim of this work is the microstructural characterization by transmission electron microscopy (TEM), of an Al-2Mg-0.6Zr (weight values) alloy, produced by powder metallurgy (hot compactation and extrusion technique), 79% cold worked, and them annealed at 623 K for several different times. Microhardness measurements were made to verify possible mechanical improvements. Differential Scanning Calorimetric (DSC) was made to verify possible range of phase transformation temperature.