Bulk tungsten with uniformly dispersed La2O3 nanoparticles sintered from co-precipitated La2O3/W nanoparticles

We report the preparation of 1 wt% La2O3 doped La2O3/W nanoparticles by a co-precipitation process, using ammonium metatungstate (AMT) and lanthanum nitrate as raw materials. The as-synthesized nanoparticles were characterized by X-ray diffraction, Filed-emission scanning electron microscopy, Transmission electron microscopy (TEM), energy dispersive spectroscopy. Our results reveal that the as-synthesized particles possess uniform diameters of about 70 nm, and are of high purity. The TEM and the corresponding fast Fourier transform images demonstrated that La2O3 precipitates were homogeneously doped into the nano-sized tungsten particles. When the as-synthesized nanoparticles were sintered by spark plasma sintering, the electron backscatter diffraction images of the bulk material reveal that La2O3 nanoparticles were homogenously distributed in both the tungsten grains and the grain boundaries, and the sample exhibit a narrow micro-hardness distribution.