The reinforcing wire production CA-60 is highly relevant due to its wide application in concrete products (welded wire mesh and truss girder), driven by growing demand for products of the construction area. One of the properties required by ABNT / NBR 7480/07 is the yield stress (σe), which has a direct effect on the maximum load that the structural component may be subjected in service. The addition of steel wire temperature during cold rolling increases the σe and reduces the ductility due to the aging phenomenon. These variations occur due to the formation of solute atoms atmosphere around the dislocations. The purpose of this paper is to study the behavior of σe during heat treatment of static aging at 100 °C in the wire CA-60 steel made from the niobium microalloyed steel equivalent ASTM A913 and the equivalent ASTM 1013 steel. As a result the wire carbon steel 1013 showed the same variation of σe during static aging of niobium microalloyed steel A913. This phenomenon was justified because of the increased level of pro-eutectoid ferrite and grain size in the carbon steel 1013.