Papers by Author: Thomas Schambron

Abstract: In this work we compare and contrast the stability of retained austenite during tensile testing of Nb-Mo-Al transformation-induced plasticity steel subjected to different thermomechanical processing schedules. The obtained microstructures were characterised using optical metallography, transmission electron microscopy and X-ray diffraction. The transformation of retained austenite to martensite under tensile loading was observed by in-situ high energy X-ray diffraction at 1ID / APS. It has been shown that the variations in the microstructure of the steel, such as volume fractions of present phases, their morphology and dimensions, play a critical role in the strain-induced transition of retained austenite to martensite.

Abstract: Achieving fine and uniform grains is the most effective way to enhance strength and toughness, which are required properties for pipeline steels. Steels microalloyed with Nb can exhibit a mixed grain structure, which can deteriorate low temperature toughness. In this work the effects of the thermomechanical processing parameters on the prior austenite grain structure before ferrite transformation have been investigated.