Graduate School

Project B14: Quantitative phase-field simulation of induction hardening in plain-carbon steels

Person in charge:  Kubendran Amos, Prince Gideon

Motivation and objectives:
During induction hardening, a workpiece is momentarily heated up to austenitisation temperature. Hardened and tempered steel with a phase mixture of ferrite and cementite is the starting material for induction hardening. During heating, the carbides dissolve due to the diffusion of the carbon atoms, the structure of the iron lattice changes, and a homogeneous austenitic microstructure with an equally distributed carbon ratio is gradually formed. Thus, in order to understand the isothermal diffusional behaviour of carbon, the morphological of cementite which is entirely governed by volume-diffusion and curvature-difference is analysed using thermodynamically consistent phase-field model.
Methods Results
  • Incorporation of CALPHAD data.
  • Large-scale three-dimensional simulation resembling the physical condition.
  • Monitoring the dissolution of carbon and corresponding morphological evolution of cementite.
  • Strenuous analysis and validation with the existing theoretical and experimental results. 
  • Acceptable agreement with existing analytical and experimental results.
  • Relaxation to some of the approximations hitherto made in theoretical treatments.
Transformation Mechanism:
  • A new transformation mechanism ensued by the cementite plate has been identified.