Microstructural evolution and mechanical behavior of porous W reinforced by in-situ W2C

Porous tungsten reinforced by W2C was prepared by tape casting using NaCl space holder. The results showed that stable W-NaCl tapes had been produced, a porous foam with a controllable porosity was finally formed. The large pores created by the space holder were 4 mu m, and the small pores induced by powder sintering were 1 mu m. The C atoms introduced by organic additives transform the powder sintering into reaction-sintering, and help the in-situ formation of the W2C ceramic phase, contributing to massive improvements in strength. With the increasing of sintering temperature, the porosity decreased and the compressive strength increased. The content of the NaCl was linear with porosity, but tended to vary inversely with the compressive strength. (C) 2019 Elsevier B.V. All rights reserved.