Toughness Deterioration in Advanced High Strength Bainitic Steels

Carbide free bainitic steels alloyed with manganese have achieved the highest strength and toughness combinations to date for bainitic steels. Ultimate tensile strengths ranging from 1600 to 1800MPa were achieved while keeping a total elongation higher than 10%. Their toughness at room temperature m...

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Detalles Bibliográficos
Autores: García Caballero, Francisca, Chao, Jesús, Cornide, Juan, García Mateo, Carlos, Santofimia, Maria Jesús
Tipo de recurso: artículo
Fecha de publicación:2009
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/34346
Acceso en línea:http://hdl.handle.net/10261/34346 doi:10.1016/j.msea.2009.06.034
Access Level:acceso abierto
Palabra clave:Banding
steel
Coalesced bainite
Toughness
Descripción
Sumario:Carbide free bainitic steels alloyed with manganese have achieved the highest strength and toughness combinations to date for bainitic steels. Ultimate tensile strengths ranging from 1600 to 1800MPa were achieved while keeping a total elongation higher than 10%. Their toughness at room temperature matches tempered martensitic steels, known to be the best-in-class regarding this property. This improvement in toughness is achieved suppressing the precipitation of cementite during bainite formation by alloying the steel with about 1.5 wt% of silicon. However, it has been observed that strongly orientated martensite bands, associated to inhomogeneous manganese redistribution during solidification, lead to a remarkable deterioration in toughness in these advanced bainitic steels. The stress concentration associated with highly heterogeneous hardness distribution in the microstructure contributes to the premature crack nucleation.