Numerical investigation of the variation of a uniformly dimensioned cast iron property using cooling channels

Abstract

Cast iron is produced by pouring of smelted metals into a mould, and is differentiated from steel by the carbon content. Different types of cast iron are available, and the properties which are used for distinguishing one from the other are formed based on the chemical composition, liquid treatment, heat treatment, and the cooling rate. The cast iron microstructure is greatly dictated by the graphite size and matrix structure which is primarily influenced by the cooling rate. Cooling rates can make or mar the cast, and are usually varied either with the use of different mould materials or by segmenting the cast. A uniform dimensioned cast with varied properties across its span using the same mould material can be made with the use of cooling channels tailored into the mould. This study seeks to numerically investigate the use of cooling channels to vary the properties of cast iron using the finite element method of solution available in COMSOL Multiphysics. The flow of a cooling fluid through the cooling channels during casting led to different cooling rates across the cast span setting up a temperature differential, an indication of varied properties within it. The cooling rate was observed to be a function of the cooling fluid entry temperature. The properties of a uniformly dimensioned cast iron can be made to vary along its span with the use of a tailored cooling channel in the mould.