Effect of zirconium and niobium on the microstructure and mechanical properties of high-strength low-alloy cast steels

Abstract The aim of this work is to study the effect zirconium and niobium on refinement grain size mechanical properties micro-alloyed cast steels in heat treated conditions. Five with different compositions, as steel without microalloying elements (i) 0.05% Zirconium (Zr), (ii) (Zr) Niobium (Nb), (iii) 0.10% (iv) (Nb) were investigated. samples are normalized at 1000 °C followed by air cooling characterized characteristics carbide precipitates SEM TEM evaluated tensile test per ASTM A370. Among these five steels, containing Zr Nb showed a higher strength 1184 MPa yield 740 reasonable impact energy 42 J compared other under same Due combined addition steel, remarkable improvement particularly was observed. As evident from microstructure investigation, improved present could be attributed due effective ferritic condition.