The goal of this work was to compare a silicon nitride-based ceramic material to a carbide tool in the face milling operation of two irregular surfaces. The main conclusions were (a) ceramic tool life was longer than carbide tool life even taking into account the higher cutting speed used when milling with ceramic and (b) ceramic tools showed a regular wear, caused mainly by diffusion, while carbide tools displayed chippings on the cutting edge. These facts prove that silicon nitride-based ceramic has enough resistance to withstand the impacts inherent to the milling of gray cast iron, even if the machined surfaces had irregularities. (c) 2007 Elsevier B.V. All rights reserved.20641699294304