On the primary solidification of compacted graphite iron: Microstructure evolution during isothermal coarsening
| العنوان: | On the primary solidification of compacted graphite iron: Microstructure evolution during isothermal coarsening |
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| المؤلفون: | Hernando, Juan Carlos, Diószegi, Attila, 1962 |
| المصدر: | Materials Science Forum. 925:90-97 |
| مصطلحات موضوعية: | Primary austenite, Microstructure evolution, Dendritic coarsening, Compacted Graphite Iron, CGI |
| الوصف: | It is widely accepted that in most commercial hypoeutectic alloys, both static mechanicalproperties and feeding characteristics during solidification, are extremely linked to the coarseness ofthe primary phase. It is therefore of critical importance to provide tools to control and predict thecoarsening process of the dendritic phase present in hypoeutectic melts. The characterization of theprimary phase, a product of the primary solidification, has traditionally been neglected whencompared to the eutectic solidification characterization in cast iron investigations. This workpresents the morphological evolution of the primary austenite present in a hypoeutectic compactedgraphite cast iron (CGI) under isothermal conditions. To that purpose, a base spheroidal graphitecast iron (SGI) material with high Mg content is re-melted in a controlled atmosphere and reversedinto a CGI melt by controlling the Mg fading. An experimental isothermal profile is applied to thesolidification process of the experimental alloy to promote an isothermal coarsening process of theprimary austenite dendrite network during solid and liquid coexistence. Through interruptedsolidification experiments, the primary austenite is preserved and observed at room temperature. Byapplication of stereological relations, the primary phase and its isothermal coarsening process arecharacterized as a function of the coarsening time applied. The microstructural evolution observedin the primary austenite in CGI and the measured morphological parameters show a similar trend tothat observed for lamellar graphite cast iron (LGI) in previous investigations. The modulus of theprimary austenite, Mγ, and the nearest distance between the centre of gravity of neighbouringaustenite particles, Dγ, followed a linear relation with the cube root of coarsening time. |
| وصف الملف: | |
| URL الوصول: | https://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-40548 https://doi.org/10.4028/www.scientific.net/MSF.925.90 |
| قاعدة البيانات: | SwePub |
| تدمد: | 02555476 16629752 |
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| DOI: | 10.4028/www.scientific.net/MSF.925.90 |