The preparation process of ultrafine gain W-Re powder by wet chemical method and its effect on alloy properties

Abstract

Tungsten-rhenium (W-10Re) powder was successfully prepared by wet chemistry method followed by spark plasma sintering technique to fabricate W-10Re alloy. The synthesis mechanism and reduction behavior of the W-10Re powders were investigated by using X-ray diffraction (XRD), thermogravimetric experiments, and X-ray photoelectron spectroscopy. The reduction process of W-10Re powders from 100 °C to 1200 °C was divided into four stages, and the optimal reduction temperature region is 1000 °C–1100 °C. The reduced powders with irregular cube-shape were examined by transmission electron microscope. The XRD results of powders reduced at 1000–1200°C showed an overall right shift with the increase in temperature, indicating the solid solution of Re into W. The microstructure and mechanical properties of the alloys were studied using XRD, transmission electron microscopy, scanning electron microscopy, and Vickers hardness. The relative densities and grain sizes were comparable for the W-10Re alloys prepared from the powders reduced at 1000 °C, 1100 °C, and 1200 °C, whereas the Vickers hardness was decreased with the increase in the reduction temperature for those samples. The characterization of fracture toughness for these W-10Re alloys showed largely intergranular fracture with a small number of transgranular features. • Tungsten rhenium powder with an irregular cube shape and evenly distributed sizes could be prepared by the wet chemical method. • The particle size, oxygen content, and formation of solid solution were related to reduction temperature. • The reduction process of the precursor was studied and analyzed, and the reason for incomplete powder reduction was proposed, which was different from earlier studies.