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arXiv · 0804.4377

The role of carbon segregation on nanocrystallisation of pearlitic steels processed by severe plastic deformation

Xavier Sauvage·Yulia Ivanisenko
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Abstract

The nanostructure and the carbon distribution in a pearlitic steel processed by torsion under high pressure was investigated by three-dimensional atom probe. In the early stage of deformation (shear strain of 62), off-stoichiometry cementite was analysed close to interphase boundaries and a strong segregation of carbon atoms along dislocation cell boundaries was observed in the ferrite. At a shear strain of 300, only few nanoscaled off-stoichiometry cementite particles remain and a nanoscaled equiaxed grain structure with a grain size of about 20 nm was revealed. 3D-AP data clearly point out a strong segregation of carbon atoms along grain boundaries. The influence of this carbon atom segregation on the nanostructure formation is discussed and a scenario accounting for the nanocrystallisation during severe plastic deformation is proposed.

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Xavier Sauvage, Yulia Ivanisenko. 2008-04-28. The role of carbon segregation on nanocrystallisation of pearlitic steels processed by severe plastic deformation. https://doi.org/10.1007/s10853-006-0750-z

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