Significant research has been conducted with the goal of obtaining thin walled ductile iron for use in lighter weight designs. A review is made of the past efforts to achieve thin walled ductile iron. Most past efforts resorted to costly processes or non-standard production practices. Lost Foam Casting (LFC) is an alternate foundry process which used in conjunction with standard melt shop practices results in a massive carbide free structure when used with thin section size. Chemistry, hardness tests, microstructures, and design improvements of a case study are reviewed.
Despite the embrace of aluminum and other nonferrous materials, steel is still a widely used material in the vehicle industry. However, it is not produced in the vehicle industry by the lost foam casting (LFC) method despite the tremendous potential benefits. These include the elimination of machining due to tolerances equal to investment casting and part consolidation which allows for the elimination of components and joining technologies. Both of these are financially and operationally beneficial by allowing for the creation of a leaner supply chain. With proper lost foam casting technology adjustments to compensate for the higher melting point of steel, there appear to be no degradation in cast steel as compared to when cast by green sand or resin bonded sand (no -bake) methods. In fact the opposite is true as the LFC benefits of improved surface roughness and dimensionality are maintained.