/Influence of a cryogenic treatment on the abrasive wear resistance of AISI/ SAE 1045 steel treated from intercritical temperatures

Abstract

Intercritical heat treatments are a new method for obtaining dual phased steels (DP). These steels have mechanical properties such as high yield stress, high strain hardening and good ductility. This combination is related to volumetric fractions of ferrite and martensite. Previous research indicates that by cryogenically treating highly alloyed steels a gain in abrasive wear resistance is obtained, but there are no previous references on intercritical heat treating followed by cryogenic treatment. During this investigation, an analysis of the influence of both treatments in abrasive wear resistance was made according to the ASTM G-65 Standard Test Method using an AISI/SAE 1045 steel, which was taken to intercritical temperatures between 740°C and 770°C for 30 minutes and then quenched. Afterwards, it was cryogenically treated to -196 °C with holding times of 24 and 48 hours. Subsequently it was tempered at 450°C for 15 and 30 minutes. An additional microstructural characterization was made and relationships between microconstituents and abrasive wear resistance were stablished. Results showed a decrease of 27% volumetric mass loss as a consequence of the heat treating compared to an untreated sample