EVALUACIÓN DE TRATAMIENTOS DE Q&P SOBRE ACEROS FUNDIDOS MEDIO CARBONO-ALTO SILICIO

Abstract

In this paper the influence of segregation patterns on the solid-state phase transformations obtained by a Q&P heat treatment performed on a 0.52% C cast steel alloyed with Cr, Mn and Si was investigated. A heat treatment scheme was carried out by total austenitization of the samples at 900°C, followed by QT=250°C quenching and partitioning (PT)= 270°C, 300°C and 350°C. Microstructural characterization of the Q&P treated samples was performed with optical microscopy (OM) and scanning electron microscopy (SEM). A maximum level of 19% of retain austenite was quantified by using the results obtained with X-ray diffraction analysis (XRD). Finally, the microsegregation of the substitutional elements was analyzed using energy dispersive X-ray spectroscopy (SEM-EDX), which led to establish the relationship between the chemical composition of the first to freeze (FTF) and the last to freeze zones (LTF), the microstructure observed, and the microhardness measured in each region.