Linking cooling conditions, pearlite characteristics, and mechanical properties in pearlitic ductile cast iron: experimental and simulation insights

Linking cooling conditions, pearlite characteristics, and mechanical properties in pearlitic ductile cast iron: experimental and simulation insights

Článek WoS

Microstructural features of ductile cast iron (DCI), including graphite morphology and the pearlitic matrix, are influenced by solidification and subsequent eutectoid transformation and can be effectively tailored through the cooling conditions. While the relationship between pearlite characteristics and mechanical properties is well established for pearlitic steels, the specific contribution of the pearlitic matrix to the mechanical response of DCI has received limited attention. In this study, fully pearlitic DCIs were cast under various cooling rates between 0.1 to 0.34 K/s, enabling systematic variations in microstructure to be correlated with changes in mechanical properties. The resulting interlamellar spacing (ILS) of the pearlite matrix ranged from 291 to 564 nm and was associated with an approximately 70 MPa difference in yield strength. A modified Hall-Petch-type relationship was formulated to describe the dependence of yield strength on ILS. To support predictive capability, representative volume elements were generated from optical micrographs and micromechanical simulations were conducted to isolate the effect of varying ILS on yield strength. The simulation results showed excellent agreement with the experiments, confirming that the ILS predominantly governs the onset of plastic deformation and that pearlite refinement is a key controlling factor for the yield strength of pearlitic DCI.

Microstructural features of ductile cast iron (DCI), including graphite morphology and the pearlitic matrix, are influenced by solidification and subsequent eutectoid transformation and can be effectively tailored through the cooling conditions. While the relationship between pearlite characteristics and mechanical properties is well established for pearlitic steels, the specific contribution of the pearlitic matrix to the mechanical response of DCI has received limited attention. In this study, fully pearlitic DCIs were cast under various cooling rates between 0.1 to 0.34 K/s, enabling systematic variations in microstructure to be correlated with changes in mechanical properties. The resulting interlamellar spacing (ILS) of the pearlite matrix ranged from 291 to 564 nm and was associated with an approximately 70 MPa difference in yield strength. A modified Hall-Petch-type relationship was formulated to describe the dependence of yield strength on ILS. To support predictive capability, representative volume elements were generated from optical micrographs and micromechanical simulations were conducted to isolate the effect of varying ILS on yield strength. The simulation results showed excellent agreement with the experiments, confirming that the ILS predominantly governs the onset of plastic deformation and that pearlite refinement is a key controlling factor for the yield strength of pearlitic DCI.

Pearlitic ductile cast iron, Pearlite interlamellar spacing, Microstructure/cooling condition correlation, Microstructure-informed simulation, Process-structure-property relationship

Pearlitic ductile cast iron, Pearlite interlamellar spacing, Microstructure/cooling condition correlation, Microstructure-informed simulation, Process-structure-property relationship

FIROOZBAKHT, M.; HORBACH, L.; WEBER, F.; ŠTĚPÁN, R.; ZHANG, J.; PUSTAL, B.; BROECKMANN, C.; BUHRIG-POLACZEK, A.

2026

01.04.2026

Elsevier

Materials & Design

264

April 2026

Spojené království Velké Británie a Severního Irska

12

https://www.sciencedirect.com/science/article/pii/S0264127526002662