Major improvements in new advanced high strength steels, especially related to microstructural features, have been made by the steel sector access trade-off between and ductility. In this context, present study provides a detailed analysis of microstructure cold rolled with minimum tensile 980 MPa, which possesses superior elongation when compared other conceptions steels from same level. The a...

The pinning effect is useful for restraining austenite grain growth in low alloy steel and improving heat affected zone toughness in welded joints. We propose a new calculation model for predicting austenite grain growth behavior. The model is mainly comprised of two theories: the solute-drag effect and the pinning effect of TiN precipitates. The calculation of the solute-drag effect is based o...

In this work, a medium Mn-Ni steel was treated through Quenching and Partitioning (Q&P) with partitioning temperature (PT) of 650 °C, which corresponded to the start austenite reverse transformation (ART) phenomenon. The influence quenching (QT) time (Pt) on stabilization mechanical properties investigated. A strong observed. Results were compared those obtained after Q&P treatment 400 ...

The evolution of the dislocation densities in martensite and austenite during quench a low-carbon (0.215 wt% C) steel is investigated situ by mean High Energy X-Ray Diffraction experiment on synchrotron beamline. line configuration offers an excellent time resolution well adapted to studied martensitic transformation kinetics. density dislocations increases as proceeds confirming that are not h...

Abstract In this work, two medium Mn steels (5.8 and 5.7 wt pct Mn) were subjected to a quenching partitioning (Q&P) treatment employing temperature which corresponded the start of austenite reverse transformation (ART). The influence 1.6 Ni addition in one cycle parameters on stability mechanical properties was also studied. High contents retained obtained lower (QT) condition, at same tim...

This work investigates the effect of a constant load on hydrogen diffusion through Q&P steel containing metastable retained austenite by combining electrochemical permeation and thermal desorption spectroscopy. Material samples are placed under different external loading conditions, ranging from 50% to 125% yield stress. The transients indicate that is delayed all stressed even at stresses in e...

Abstract. Low-alloy TRIP steel sheets with ultra-high-strength that utilize transformation-induced plasticity of retained austenite have high strength and ductility. In this study, low-alloy thermo-mechanical treatment warm rolling were prepared, the effects on tensile properties investigated. A hot-rolled sheet Ms 418.5°C was austenized then quenched in a salt bath kept at 450°C. Two specimens...