Precipitation during hot rolling and cooling
|Coordinator||Uppsala Synchrotronix AB - c/o Edwards Science & Technology AB|
|Funding from Vinnova||SEK 499 000|
|Project duration||February 2020 - December 2021|
|Venture||Research infrastructure - utilisation and collaboration|
|Call||Industrial pilot projects for the utilisation of neutron and photon based techniques at large-scale infrastructures - Autumn 2019|
Purpose and goal
Together with Lund University, Swerim and Uppsala Synchrotronix, SSAB will investigate the possibility of studying nanometer-small precipitates in microlloyed steels. The aim is to study the precipitation kinetics and interactions with recrystallization and phase transformation during high temperature deformation and during cooling, in-situ. The knowledge will be used to optimize hot rolling and steel alloys. By using combined SAXS and WAXS measurements, the size distribution of precipitates can be measured simultaneously as recrystallization or phase transformation.
Expected results and effects
The measurements will give more knowledge about precipitation and their interaction with recrystallization and phase transformation. Being able to study these processes directly during hot deformation and cooling in a hot rolling simulation device would provide invaluable information for filling in the knowledge gaps regarding the material behavior during hot deformation of microlloyed steels. The results can be used for further development of microstructure evolution models for microalloyed steels. This enables more efficient optimization of the hot rolling process.
Planned approach and implementation
As a first step, measurements will be made ex-situ to verify that particle size distribution and crystal structure of specific particles (Nb and Ti rich carbides and carbonitrides) can be measured with combined SAXS and WAXS. Samples for ex-situ measurements will be made in a dilatometer where the samples are quenched at different stages after simulated hot rolling. In-situ measurements will then be conducted at the Petra III synchrotron in Hamburg, preferably in P07 where a dilatometer is installed and then in a customized test equipment in P21. Data analysis and evaluation will be done continuously.