ICME-based process and alloy design for vacuum carburized steel components with high potential of reduced distortion
This project aims the development of an energetic efficient production of forged components from micro alloyed dual phase steel with reduced distortion.
Carburized steel components are usually quenched from hardening temperature in a complete austenitic phase to room temperature. This leads to a microstructure comprised of almost martensite plus bainite giving rise to unwanted heat-treatment induced distortion. However, having a soft phase of ferrite dispersed throughout the microstructure can be quite effective in this regard. This is attributed to the capability of ferrite in accommodating the plasticity resulted from austenite-to-martensite transformation expansion. In the context of this project, it is demonstrated that how a proper selection of chemical compositions and a hardening temperature can greatly suppress the associated distortion.
In order to design a new steel alloy systematically, which fits to the above-mentioned conditions, an ICME-based methodology has been employed. Thus, a series of calculations have been carried out utilizing the thermodynamic-based software Thermo-Calc controlled within a framework written in Python. For the most promising alloy, the austenite-to-ferrite phase transformation kinetics are predicted using the software DICTRA. This yields to generate virtual Time-Temperature-Transformation TTT diagrams depending on the local carbon content. The carburizing process, the phase transformations and the effect of the created microstructure on the final distortion are simulated in macro-scale through FE-software Simufact.forming taing into account the local varying TTT diagrams within the carbon diffusion zone. Finally, the simulation outcomes are validated experimentally by employing Navy C-Ring specimens.
Steel Institute IEHK,
RWTH Aachen University
|Simufact Engineering GmbH||Tempowerkring 19,
Department of Metallurgical and Materials Engineering,
Indian Institute of Technology Madras
Tata Consultancy Services TCS
- U. Prahl, H. Farivar: Combined Process and Alloy Design of a micro-alloyed DP Forging Steel Based on ICME (DP-Forge), Simufact Round Table, Marburg, Germany 2016.
- H. Farivar , G. Rothenbucher, U. Prahl, R. Bernhardt: ICME-based process and alloy design for vacuum carburized steel components with high potential of reduced distortion, 4th World Congress on Integrated Computational Materials Engineering (ICME 2017), Ypsilanti, Michigan, USA 2017.
- D. M. John, H. Farivar, G. Rothenbucher, R. Kumar, P. Zagade, D. Khan, A. Babu, BP Gautham, R. Bernhardt, G. Phanikumar, U. Prahl: An attempt to integrate software tools at microscale and above towards an ICME approach for heat treatment of a DP steel gear with reduced distortion, 4th World Congress on Integrated Computational Materials Engineering (ICME 2017), Ypsilanti, Michigan, USA 2017.