Impact of composition and fabrication method on the corrosion behavior of tungsten heavy alloys in aqueous solutions.

Tungsten heavy alloys (WHAs) are kind of composite materials; these alloys provide a unique combination of properties such as high density, excellent mechanical properties and good corrosion resistance that making them increasingly attractive in many practical applications. In this work, the corrosion behavior of the investigated tungsten heavy alloys with the composition of (95% W-3.5% Ni-1.5% Fe), (93% W-4.5% Ni-1.0% Fe-1.5% Co) and (90% W-6% Ni-4% Cu) fabricated by either chemical or mechanical technique has been evaluated through potentiodynamic polarization measurements in different aqueous solutions of 0.6 M NaCl, 0.1 M HCl and 0.1 M NaOH. The extent of the corrosion has been illustrated by examining the surfaces of WHAs before and after the corrosion test using SEM. It includes general dissolution, localized attack of the binder phase and tungsten grain loss, where the extent of each of these depends on the fabrication technique and the alloy composition as well as the pH of the medium. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]