An evaluation of some properties of borides deposited on boronized ductile iron

Abstract

In this study, some properties of borided perlitic ductile irons were investigated. Boronizing was realized in a salt bath and appropriate boronizing heat treatment was carried out between under atmospheric pressure. Borides e.g. FeB, Fe2B formed on ductile iron was verified by x-ray diffraction (XRD) analysis, SEM and optical microscope. The distribution of alloying elements was detected by means of energy dispersive x-ray spectroscopy (EDAX) from the surface to the interior. Experimental results revealed that longer boronizing time resulted in thicker boride layers. Optical microscope cross-sectional observation of borided layers showed dentricular morphology. Both hardness and fracture toughness of boronized surfaces were measured via Vickers indenter. The micro-Vickers hardnesses of borides formed on the ductile iron were in the range of 1160-2140 VHN and fracture toughness were in the range of 2.19-4.47 MPa m(1/2). (C) 2004 Elsevier B.V. All rights reserved.