Powder Technology, Vol.283, 401-405, 2015
Fabrication of tungsten-based composites by solid binder mixing and sintering
A new solid binder mixing technique is investigated for the fabrication of net-shaped tungsten-based composite in this paper. Sub-micron tungsten-based composite and paraffin wax (PW) powders are mechanically milled at room temperature. The composite powders homogeneously encompass the PW powders, reducing the PW volume fraction to 0.2 for the production of a sound tube-type compact under an ambient condition with a pressure of 200 MPa. The dimensions of the compact after the thermal debinding process are rarely changed. Further advantages of the technique are observed for the sintered sample. A volumetric decrease of the composite corresponds to the initial PW binder volume fraction, and dimensional shrinkages are equivalent in all directions. The net-shaped composite shows a reasonable mechanical property, as well as that of the simple-shaped composite without the PW. Therefore, the process of mechanical binder dispersion in the tungsten-based composite powder, suggested in this study, is very effective for net-shaped composite production. (C) 2015 Elsevier B.V. All rights reserved.
Keywords:Tungsten-based composite;Paraffin wax binder;Mechanical milling;Sintering;Isotropic shrinkage