The effects of bimodal grain size distributions on the work hardening behavior of a TRansformation-TWinning induced plasticity steel

The effects of bimodal grain size distributions on the mechanical properties of a newly developed TRansformation-TWinning induced plasticity (TRIP/TWIP) steel were investigated. The microstructures with different levels of bimodal grain size distributions were achieved through rolling at 1000, 1100...

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Detalles Bibliográficos
Autores: Eskandari Sabzi, H., Zarei Hanzaki, A, Abedi, H. R., Soltani, R., Mateo García, Antonio Manuel|||0000-0001-8336-6128, Roa Rovira, Joan Josep|||0000-0002-7440-0766
Tipo de recurso: artículo
Fecha de publicación:2016
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/91330
Acceso en línea:https://hdl.handle.net/2117/91330
https://dx.doi.org/10.1016/j.msea.2016.09.085
Access Level:acceso abierto
Palabra clave:Steel--Heat treatment
Steel, High strength
TRansformation-TWinning induced plasticity steel
mechanical twinning
martensitic transformation
bimodality
work hardening behavior
Acer -- Tractament tèrmic
Acer d'alta resistència
Acer austenític
Àrees temàtiques de la UPC::Enginyeria dels materials
Descripción
Sumario:The effects of bimodal grain size distributions on the mechanical properties of a newly developed TRansformation-TWinning induced plasticity (TRIP/TWIP) steel were investigated. The microstructures with different levels of bimodal grain size distributions were achieved through rolling at 1000, 1100 and 1200 °C where the restoration processes (in particular recrystallization) could be occurred at different rates. The results indicated that the bimodal distribution parameter was increased by raising the rolling temperature and lowering the thickness reduction. In addition, the room temperature strength and ductility were higher for the materials rolled at higher temperatures, where the level of bimodal grain size distributions (bimodality) was greater. This was justified considering the higher possibility of strain induced transformation and twinning in coarser grains than that of finer ones; this in fact would dictate the material work hardening potential during subsequent tensile deformation. For the material rolled at 1000 °C, where the grain size distributions were more homogeneous and the level of bimodal distributions was low, the austenite to martensite transformation during tensile deformation at room temperature was the prevailing mechanism to induce the plasticity. In contrast, in the materials rolled at 1100 and 1200 °C the mechanical twinning came into action thereby a rapid hardening region was recognized in their work hardening behavior. These effects were correlated to the length of work hardening region (dictated by twinning), and the magnitude of hardening rate (controlled by transformation of austenite to a' martensite).