Numerical simulation of solidification structure during electroslag remelting casting of ZG06Cr13Ni4Mo ingot based on CAFE and moving boundary method

Abstract

A comprehensive mathematical model of the solidification structure during the process of electroslag remelting casting (ESRC) of low carbon martensite stainless steel ZG06Cr13Ni4Mo has been established. The change of metal pool profile and grain growth and the microstructure evolution process from the beginning to the steady stage of the ESRC process were investigated by using the moving boundary method and the coupled technology CAFE method (cellular automaton – finite element method). The transition from equiaxed grains at the lateral wall of the mould to columnar grains has been revealed. In addition, casting of this steel has been carried out and the microstructure of the ingot obtained after grinding and acid leaching. According to the comparison of the metal pool profile, morphology and growth direction of the dendrite and the secondary dendrite arm spacing (SDAS) between the experimental results and the simulation results, the validity of the model has been demonstrated, which can provide a favourable theoretical foundation to optimise the process parameters for the control of solidification structure of ESRC of low carbon martensite stainless steel ZG06Cr13Ni4Mo.

Keywords:

• Electroslag remelting casting
• ZG06Cr13Ni4Mo
• CAFE method
• Solidification
• Microstructure
• Secondary dendrite arm spacing

Acknowledgements

This work is supported by National Nature Science Foundation of China (grant no. 51204041) and the Fundamental Research Funds for the Central Universities (grant nos. N130402016 and N140204014) for support as well as to Program for Liaoning's Innovative Research Team in University (grant no. LT20120008).