Mode I fatigue crack growth with a superimposed static torque was investigated in bainitic steel. The had little effect on kinetics and path. However, the non-singular stress parallel to front, bending stresses due eccentric triggered twisting, even mode I. A progressive increase sliding displacement rise elastic torsional compliance, but also plastic ratchetting at tip, shearing of face asperi...

Abstract The microstructure of a low alloy medium carbon bainitic steel, austempered in the temperature range 275 °C to 450 has been investigated by detailed electron backscatter diffraction and variant pairing analysis. It is observed that tendency two distinct changes with varying temperature. At V1-V6 most frequent, whereas V1-V2 frequent at intermediate highest temperature, V1-V4 dominates....

Abstract The work presents results on the effect of prior martensite formation bainite transformation kinetics in a 3% medium-Mn multiphase steel. material was subjected to two isothermal holding temperatures: 400 °C (without martensite) and 350 (with martensite). According obtained dilatometric results, leads acceleration kinetics. starts finishes much faster, when present before holding. micr...

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...

A bainitic microstructure with fine ferrite plates (20 to 40 nm) in a matrix of high-carbon retained austenite, obtained by isothermal transformation at 200°C, was characterized with an energy-compensated optical position-sensitive three-dimensional atom probe. The average carbon concentration in the austenite was found to be 8.0±1.6 at.% and in the bainitic ferrite 1.1±0.7 at.%. The latter con...

The tempering of two–phase mixtures of bainitic ferrite and carbon–enriched retained austenite has been investigated in an effort to separate the reactions that occur at elevated temperatures from any transformation during cooling to ambient conditions. It is demonstrated using synchrotron X–radiation measurements, that the residue of austenite left at the tempering temperature partly decompose...

The effect of deformation temperature on the mechanical properties 1-GPa-grade TRIP steels with different retained austenite (?R) morphologies was studied. dependence deformation-induced martensitic transformation behavior also investigated. uniform elongation below room relatively large in needle-like ?R steel, whereas tensile strength at each almost same as it independent morphology. better s...