Secondary graphitization kinetics in a gray cast iron
Paulo Henrique Ogata, Wilson Luiz Guesser, Hélio Goldenstein
Abstract
This work aims to study the solid state graphite precipitation on a grey cast iron during isothermal martensite tempering treatments at high temperatures, a phenomenon known as “secondary graphitization”. Samples austenitized at 900 °C and quenched with He, were heated up to 650 °C and maintained at this temperature on a quenching dilatometer. Reactions during heating and during isothermal maintenance were detected through volumetric changes. Kinetics results were interpreted using Burke and Swindells equations.
Keywords
Referências
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Submetido em:
17/09/2021
Aceito em:
03/02/2022
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