M. Ahangarkani, K. Zangeneh-Madar, H. Abbaszadeh, A. A. Rahmani , S. Borgi,
Volume 11, Issue 3 (september 2014)
Abstract
In the present paper, the influence of cobalt additive on the sintering/infiltration behavior of W-Cu composite
was studied. For this purpose, the mixed powders of tungsten and cobalt were compacted by CIP method and then
sintered at 1450, 1550 and 1600 °C in a hydrogen atmosphere. The sintered specimens at 1550 °C were subsequently
infiltrated with liquid copper at 1250 °C for 10, 60 and 120 min. The microstructure and composition of samples were
evaluated using SEM, EDS as well as XRD techniques. The density of the sintered samples was measured by
Archimedes method. Vickers indentation test was used to measurement hardness. It was found that sintering
mechanism of tungsten powder depends on temperature and cobalt additive content. Also, the best infiltration behavior
was observed in the samples with optimum cobalt value. In addition, it was found that the W-W contiguity as well as
dihedral angle decreases as cobalt increases. Density and hardness of infiltrated specimens are attained 16.28-16.79
g.cm-3 and 220-251 VHN, respectively.
