Design of Cold Rolled and Continuous Annealed Carbide-Free Bainitic Steels for automotive application
Advanced high strength steels for automotive applications were designed to achieve a carbide-free bainitic microstructure after conventional thermo-mechanical processing and a continuous annealing treatment. The microstructure obtained consists of ferrite laths interwoven with thin films of untransf...
| Autores: | , , , , , |
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| Tipo de recurso: | artículo |
| Fecha de publicación: | 2013 |
| País: | España |
| Institución: | Consejo Superior de Investigaciones Científicas (CSIC) |
| Repositorio: | DIGITAL.CSIC. Repositorio Institucional del CSIC |
| OAI Identifier: | oai:digital.csic.es:10261/72620 |
| Acceso en línea: | http://hdl.handle.net/10261/72620 |
| Access Level: | acceso abierto |
| Palabra clave: | Carbide-free bainite Steel Annealing Automotive components Ductility Formability |
| Sumario: | Advanced high strength steels for automotive applications were designed to achieve a carbide-free bainitic microstructure after conventional thermo-mechanical processing and a continuous annealing treatment. The microstructure obtained consists of ferrite laths interwoven with thin films of untransformed retained austenite. The sufficiently tough matrix and the control of the heterogeneity in the microstructure will allow an optimum combination of strength, ductility, and formability to be achieved. The designed steels reached far higher uniform elongations than that in commercial dual phase steels and martensitic steels with the same range of ultimate tensile strengths. Their formability was found to be appropriate for the production of final parts after cold-stamping or cold-forming. On the other hand, the yield strength/ultimate tensile strengths ratio was found to remain roughly constant (∼0.7). The reduction of area value did not seem to change as a function of overaging temperature, but the V-bending angle and the hole expansion ratio (cut-edge stretching ability) decreased significantly at the bainite holding temperature increases |
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