Complementary use of transmission electron microscopy and atom probe tomography for the examination of plastic accommodation in nanocrystalline bainitic steels

A displacive transformation involves the motion of a glissile interface. As in work hardening, its motion can be halted by defects such as dislocations, stacking faults or twins in the austenite. The defects are created when the shape deformation accompanying bainite growth is accommodated by plasti...

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Detalhes bibliográficos
Autores: García Caballero, Francisca, Yen, Hung-Wei, Miller, Michael K., Yang, Jer-Ren, Cornide, Juan, García Mateo, Carlos
Formato: artículo
Fecha de publicación:2011
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/65478
Acesso em linha:http://hdl.handle.net/10261/65478
Access Level:acceso abierto
Palavra-chave:Steels
Bainite
Transmission electron microscopy
Three-dimensional atom probe
Descrição
Resumo:A displacive transformation involves the motion of a glissile interface. As in work hardening, its motion can be halted by defects such as dislocations, stacking faults or twins in the austenite. The defects are created when the shape deformation accompanying bainite growth is accommodated by plastic relaxation of the surrounding austenite. The growing plate stops when it collides with the austenite grain boundary. Because transformation from strong austenite leads to fine plates, alloys can be designed such that the bainite transformation is suppressed to low temperatures (125–350 C), leading to a nanoscale bainitic microstructure. Complementary high-resolution transmission electron microscopy and atom probe tomography have provided new experimental evidence on the accommodation of transformation strain, a subject critically relevant to understanding the atomic mechanisms controlling bainitic ferrite growth