MODELOS MATEMÁTICOS PARA A EVOLUÇÃO DA MICROESTRUTURA NA LAMINAÇÃO DE TUBOS SEM COSTURA
MATHEMATICAL MODELS FOR MICROSTRUCTURE EVOLUTION IN THE SEAMLESS TUBE ROLLING
Carvalho, Ricardo Nolasco; Ferreira, Marcelo Almeida C.; Santos, Dagoberto Brandão; Barbosa, Ronaldo Antônio N. M.
http://dx.doi.org/10.4322/tmm.2013.030
Tecnol. Metal. Mater. Min., vol.10, n3, p.207-214, 2013
Resumo
O objetivo deste trabalho é apresentar os recentes desenvolvimentos em modelagem matemática para a evolução da microestrutura de diversos tipos de aços, aplicados à laminação contínua de tubos sem costura. O desenvolvimento desses modelos depende de uma cuidadosa caracterização do ciclo termomecânico e da correta seleção e ajuste das equações que descrevem os diversos fenômenos metalúrgicos envolvidos. Os ajustes desses modelos são elaborados utilizando-se resultados obtidos em simulação por torção a quente. Para isso, os ciclos termomecânicos são simplificados considerando-se as limitações do equipamento em reproduzir algumas deformações, velocidades de deformação e velocidades de resfriamento desenvolvidas industrialmente. Amostras para microscopia óptica foram obtidas através da interrupção das simulações depois de determinadas etapas. Após ajuste de cada modelo com os resultados obtidos na simulação, as microestruturas finais são comparadas com aquelas obtidas em escala industrial. De modo geral, são observadas boas correlações
Palavras-chave
Ensaio de torção a quente, Laminação, Tubo sem costura, Modelamento microestrutural
Abstract
The goal of this work is to present recent developments on mathematical modeling for microstructure evolution in different steel types, applied to a continuous rolling of seamless tubes. The development of these models depends on careful characterization of the thermomechanical cycle and/on correct selection and adjustment of equations which describes the several metallurgical phenomena involved on this process. The adjustments of these models are done using the results obtained in hot torsion simulations. For this, the thermomechanical cycles are simplified considering the equipment limitations in reproduce some strain, strain rates and cooling rates developed industrially. Samples for optical microscopy were obtained by interruption of simulations after selected steps of process. After adjustment of each model with results from simulation, the final microstructures are compared with those obtained in industrial scale. In general, good correlations are observed.
Keywords
Hot torsion test, Rolling, Seamless tube, Microstructure modeling
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