Characterisation and modelling of strain-induced precipitation - Camsip
This project studied the Characterisation and Modelling of Strain Induced Precipitation (CAMSIP) using the latest available laboratory simulators, analysis techniques and physically based models. A round robin series of experiments on a laboratory Fe-Nb-C microalloyed steel using all of the different thermomechanical simulators available to the partners (hot torsion, Gleeble welding simulators, plastodilatometers, high speed plane strain compression machines) showed that the different techniques are essentially compatible and provided reliable data for modelling. A joint paper detailing the main results of this work was submitted to the "Microalloying for New Steel Processes and Applications 2005" conference in San Sebastian. Software implementations of the new physically based Zurob-Hutchinson model describing the interaction of recrystallisation, recovery and precipitation in strained austenite and the semi-empirical Dutta and Sellars model were written and compared with published data. Several problems with the kinetics of recrystallisation in the Zurob model were identified and resolved after discussions with the author. The Zurob model was then calibrated using the round robin data and gave satisfactory results on this and other steel grades. Nevertheless, the final values of some of the fitting parameters were non-physical, so more development is required in this area. Further experimental work on industrial compositions revealed the strong effect of residual elements, especially Nitrogen, on strain induced Nb precipitation kinetics. Multiple hit plane strain compression tests suggest that, for a constant total strain level, multiple passes can accelerate strain induced precipitation of Nb. It is therefore possible that Nb microalloyed steels with nitrogen contents in the range of 45 wt ppm could show strain induced precipitation in a real finishing train.
Bibliographic Reference: EUR 22431 EN (2006), 112 pp. Euro: 25
Availability: Katalogue Number: KI-NA-22431-EN-S The paper version can be ordered online and the PDF version downloaded at: http://bookshop.europa.eu
ISBN: ISBN: 92-79-03740-4
Record Number: 200719270 / Last updated on: 2007-07-10
Original language: en
Available languages: en