Effects of TiN and AlN Nanoparticles in Hot Deformation of Austenite in Steels

Recrystallisation kinetics of two low-carbon steels, of which one with Ti and the other with Al as precipitate-forming elements was studied by means of hot torsion tests. The mean size of TiN and AlN particles that precipitate during hot deformation was analysed by transmission electron microscopy (TEM). These results, along with the determination of the activation energy, the precipitated volume fraction and the diffusion coefficients of Ti, Al and N in austenite explain the ineffectiveness of these particles to inhibit the static recrystallisation.

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