The effect of Cr on the properties and sintering of W skeleton as an activated element

Tungsten skeletons were fabricated by the activated sintering technique at 1050 °C, 1150 °C and 1300 °C. Cr and Cu elements with different mass ratios were selected to be the sintering activators. The interfaces of sintered W skeletons with Cr additives were characterized by EPMA attached to SEM. The compressive properties of sintered W skeleton were tested, and fracture morphologies of the porous W skeletons were examined by SEM. The results show that the addition of element Cr resulted in a W–Cr solid solution transition layer at the W interparticle grain boundaries. When the sintering temperature being above the melting point of copper, the molten phase acted as carrier and promoted the formation of sintering necks of tungsten skeleton, and the distribution of pores became more uniform with increasing the mass ratio of Cu to Cr. The compressive strength of W skeleton sintered at 1300 °C was enhanced to 283 MPa when the mass ratio of Cu to Cr was 60:1.