Ductile and High Strength White Cast Iron of Ultrafine Interconnected Network Morphology

Fe100-xCx melts (x = 18 to 24) can be cast under B2O3 flux into solids of interconnected network morphology, with a wavelength in the submicron range. There are two major constituent subnetworks, which are a brittle Fe3C subnetwork and a ductile alpha Fe subnetwork. The Fe100-xCx network alloys, therefore, are white cast iron of novel microstructure. Fe100-xCx specimens of x = 18 to 21 are ductile and the yield strength can be as large as similar to 3200 MPa. Fe100-xCx specimens of x = 22 to 24 are in the regime of a ductile-to-brittle transition. The compressive strength is high, at similar to 2700 MPa. Microstructural analysis indicates that the ultrafine network morphology and the ductile aFe subnetwork are responsible for the ductility exhibited in Fe100-xCx network alloys of x = 17 to 21. They are also responsible for the high compressive strength in Fe100-xCx network alloys of x = 22 to 24.