• Çelik, G. A.
• Tzini, M.-I.
• Aristeidakis, J.
• Atapek, Ş. H.
• Sarafoglou, P. I.
• Haidemenopoulos, G. N.
• Polat, Ş.

Abstract

<jats:p>High silicon and molybdenum ductile cast irons (Si-Mo alloys) are commonlyused as exhaust manifold materials suffering from high temperature-oxidationand thermal-mechanical fatigue. The structural integrity of cast Si-Moalloys under these service conditions is attributed to their microstructureconsisting of spheroidal graphite and Mo-rich carbide embedded in a ferriticmatrix. However, the cast structure includes also pearlite structure havinga detrimental effect on the mechanical properties, therefore the cast matrixneeds to be heat treated. In this study, the solidification of a Si-Moductile iron was investigated using (i) thermodynamic and kineticcalculations by Thermo-Calc and DICTRA software and (ii) thermal analysis inorder to reveal out the sequence of phase formation and the phasetransformations during solidification and (iii) microanalysis by energydispersive spectrometer in order to determine elemental segregation andcompare with the calculated values. The solidified structure was alsocharacterized and all microstructural features were specified.</jats:p>

Topics

• impedance spectroscopy
• molybdenum
• phase
• simulation
• carbide
• fatigue
• thermal analysis
• Silicon
• iron
• cast iron
• solidification