Optimization of mechanical properties of high-carbon pearlitic steels withSi and V additions

Systematic research has been undertaken on the effects of single and combin ed additions of vanadium and silicon on the mechanical properties of pearli tic steels being developed for wire rod production. Mechanical test results demonstrate that the alloy additions are beneficial to the mechanical prop erties of the steels, especially the tensile strength. Silicon strengthens pearlite mainly by solid-solution strengthening of the ferrite phase. Vanad ium increases the strength of pearlite mainly by precipitation strengthenin g of the pearlitic ferrite. When added separately, these elements produce r elatively greater strengthening at higher transformation temperatures. When added in combination the behavior is different, and substantial strength i ncrements are produced at all transformation temperatures studied (550 degr eesC to 650 degreesC). The addition of silicon and vanadium to very-high-ca rbon steels (>0.8 wt pet C) also suppresses the formation of a network of c ontinuous 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-m m-diameter wires.