Systematic research has been undertaken on the effects of single and combined additions of vanadium and silicon on the mechanical properties of pearlitic steels being developed for wire rod production. Mechanical test results demonstrate that the alloy additions are beneficial to the mechanical properties of the steels, especially the tensile strength. Silicon strengthens pearlite mainly by solid-solution strengthening of the ferrite phase. Vanadium increases the strength of pearlite mainly by precipitation strengthening of the pearlitic ferrite. When added separately, these dements produce relatively greater strengthening at higher transformation temperatures. When added in combination the behavior is different, and substantial strength increments are produced at all transformation temperatures studied (550 deg C to 650 deg C). The addition of silicon and vanadium to very-high-carbon steels (>0.8 wt pct C) also suppresses the formation of a network of continuous grain-boundary cementite, so that these hypereutectoid materials have high strength coupled with adequate ductility for cold drawing. A wire-drawing trial showed that total drawing reductions in area of 90 pet could be obtained, leading to final tensile strengths of up to 2540 MPa in 3.3-mm-diameter wires.
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