MICROMECHANICAL MODELING OF FERRITIC/PEARLITIC NODULAR CAST IRON

摘要

One of the main factors in determining the different grades of ductile iron is the matrix structure. In the as-cast condition, the matrix will consist of varying proportions of pearlite and ferrite, and as the amount of pearlite increases, the strength and hardness of the iron also increase. Three different nodular cast irons are here considered and two alternative micromechanics modeling approaches are then introduced and applied to predict the experimental behavior i) an axisymmetric unit cell model and ii) a microstructural finite element model. Both models predict the change of mechanical response of nodular cast iron as a function of the ferrite-to-pearlite ratio in the matrix. The mechanical response of the axisymmetric unit cell model is stiffer that of an equivalent microstructural finite element model.