Abstract: A steel member, essentially rectangular in cross-section, obtained by mechanically working round steel stock, having an aspect ratio greater than 2, wherein the member is characterized by a tensile strength greater than 200 KSI, a fatigue endurance limit greater than 100 KSI and a heat treated microstructure of tempered martensite, bainite or mixtures thereof.A method is disclosed for making a steel member comprising the steps of providing steel stock with a round cross-section having a pearlitic microstructure and at least 0.35 percent carbon, forming an essentially rectangular member having an aspect ratio of at least 2 and heat treating the member so as to provide a microstructure of tempered martensite, bainite or mixtures thereof.

Abstract: A method for producing steel filaments having a heat treated microstructure is disclosed. The method comprises the steps of providing a steel coil having a carbon content from about 0.30 to about 0.95, percent by weight, scoring the surface of the steel to form a plurality of grooves that delineate continuous longitudinal segments, heat treating the steel to develop an appropriate metallurgical structure, separating the segments into individual filaments by causing the steel to fracture at the grooves, and then passing the filaments through a mechanical straightener.