The invention relates to a READY FOR USE COMPOUND FOR A STEEL WIRE microalloyed with a structure consisting almost entirely tempered martensite FORGED IN COLD. The wire diameter is at least 0.10 mm and not more than 0.50mm. It HAS BREAKING STRENGTH OF AT LEAST 2,800 MPA. PROCEDURE FOR OBTAINING THIS wire comprises the deformation of a wire rod, HEAT TREATMENT TEMPLE AND DEFORMED WIRE heating to a tempering temperature to cause formation of a structure consisting almost entirely tempered martensite. Then cooled wire and deformed. The invention also concerns ASSEMBLIES including at least one wire of this kind. THESE WIRES OR JOINTS USED IN PARTICULAR TO REINFORCE THE COVERS OF TIRES.