Cementite dissolution in hypereutectoid steels containing Cr is analyzed using dilatometry combined with the consideration of the carbon content in the austenite. The results suggest that the austenite transformed from the mixture of ferrite and cementite can be approximated to have a carbon content corresponding to equilibrium with ferrite. The overall dissolution behavior of cementite is desc...

The effect of ferrite grain size on the fatigue and tensile properties of dual phase steels with a 0.25 volume fraction of martensite (Vm) under different heat treatments was investigated. The heat treatments were homogenized at 1200 oC along with several subsequent normalizations at 910 oC, resulting in different microstructures and mechanical properties. After heat treatment, the obtained ste...

The carbon contents in carburized steels were investigated by electron probe microanalysis (EPMA) for a range of carbon levels in the solid solution less than 1 wt%. This article describes the difficulties encountered with the classic analytical procedure using the k ratio of X-ray intensities and the phi(rhoz) model. Here, a suitable calibration curve method is presented with emphasis on the m...

Steels applied in the automotive industry can be classified under the AHSS category, which includes dual-phase (DP) steels, complex-phase (CP) steels and transformation-induced plasticity (TRIP) steels. The UHSS category mainly includes martensitic steels. The above-mentioned steel groups are well pressable, show an excellent combination of strength, service life and absorption of strain energy...

The effect of microstructural refinement and intercritical annealing on the mechanical properties and work-hardening response of a low carbon St12 steel was studied. It was revealed that intercritical annealing of the ferritic-pearlitic sheet results in the formation of a coarse-grained DP microstructure with discrete martensite islands normally formed in place of pearlitic colonies, which resu...

The present study was carried out to investigate the effect of alloying elements and thermo-mechanical treatment (TMT) i.e. hot rolling and forging with different reduction ratios on the hardness (HV) and impact toughness (J) of heat-treated low alloy steels. An understanding of the combined effect of TMT and alloying elements and by measuring hardness, impact toughness, resulting from differen...

In recent years, there has been a growing interest in steels of multi-phase structures, composed of a ferritic matrix, in which islets occur, that contain bainite-B, martensite-M and the untransformed austenite-A 1-9 . The multi-phase structure of steel with untransformed austenite promotes the increase of plasticity induced by the phase transformation – the TRIP effect 3-4, 6-8 . In steels con...

The metallic low and intermediate level radioactive waste generally consists of carbon steel and stainless steels. The corrosion rate of carbon steel in deep groundwater is typically low, unless the water is very acidic or microbial activity in the environment is high. Therefore, the assessment of microbially induced corrosion of carbon steel in deep bedrock environment has become important for...

This paper presents a study of the quasi-static and dynamic deformation behaviors of conventional and microalloyed medium-carbon steels in a wide temperature range. As strain rate increased, the flow stress increased at room temperature, but occasionally did not at elevated temperatures. The flow stress of the microalloyed steel containing precipitates was less sensitive to strain rate at room ...

The purpose of this research is to develop a model for the ferrite-to-austenite transformation on heating which would include the possibility of the change in the character of the transformation from diffusional to mixed-mode and would be less computationally demanding. A physics-based model is constructed for the ferrite-austenite phase transformation of low carbon steels. The model is descret...