Thermomechanical behaviour modelling and microstructure evolution of high Cr-Co-Mo aerospace bearing steel

The microstructure evolution and hot-compressive behaviour of high Cr-Co-Mo bearing steel under different deformation conditions were investigated by dynamic recrystallisation (DRX) kinetics analysis and simulation. The results showed that the thermal deformation parameters and carbide dissolution have a great influence on the rheological properties and microstructure. The flow stress decreases with the increase of temperature and the decrease of strain rate. The grain boundary pinning effect is weakened by the dissolution of carbides into the matrix, resulting in the rapid growth of DRX grains. The processing map of high Cr-Co-Mo bearing steel was divided into five regions, and the most suitable processing parameters can be defined as the temperature range of 1000-1070 degrees C and strain rate range of 0.01-0.003 s(-1).

Automated summary

The microstructure evolution and hot-compressive behaviour of high Cr-Co-Mo bearing steel under different deformation conditions were studied. The results showed that thermal deformation parameters and carbide dissolution have significant effects on rheological properties and microstructure. The flow stress decreases with increasing temperature and decreasing strain rate. The growth of DRX grains is facilitated by the dissolution of carbides, weakening the grain boundary pinning effect. The processing map of high Cr-Co-Mo bearing steel was divided into five regions, with the most suitable processing parameters defined as a temperature range of 1000-1070 degrees C and strain rate range of 0.01-0.003 s(-1).