Characterization of ODS-tungsten microwave-sintered from sol–gel prepared nano-powders

Nano-sized W–1%La2O3 and W–1%Y2O3 powders were synthesized by sol–gel method followed by hydrogen reduction. The average particle size of the powders is smaller than 50 nm. Microwave sintering method was used for the consolidation of tungsten samples, and a relatively low sintering temperature (1500 °C) and short soaking time (30 min) were used to reduce the grains growth. Nano-sized oxide particles with a size distribution of 10–50 nm were homogeneously dispersed in the tungsten matrix. The relative density, average grain size and Vickers micro-hardness of the microwave-sintered W–1%La2O3 and W–1%Y2O3 samples are 92.4% and 93.6%, 1.1 and 0.7 μm, 6.03 and 4.12 GPa, respectively. The W–1%Y2O3 samples showed better sinterability, finer grains, and higher hardness than the W–1%La2O3 samples.