A wet-chemical method combined with spark plasma sintering was used to prepare a W–Y₂O₃ alloy. High-temperature tensile tests and nano-indentation microhardness tests were used to characterize the mechanical properties of the alloy. After He-ion irradiation, fuzz and He bubbles were observed on the irradiated surface. The irradiation embrittlement was reflected by the crack indentations formed during the microhardness tests. A phase transformation from α-W to γ-W was investigated by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Polycrystallization and amorphization were also observed in the irradiation damage layer. The W materials tended to exhibit lattice distortion, amorphization, polycrystallization and phase transformation under He-ion irradiation. The transformation mechanism predicted by the atomic lattice model was consistent with the available experimental observations. These findings clarify the mechanism of the structural transition of W under ion irradiation and provide a clue for identifying materials with greater irradiation resistance.

Pure W and W-(2%, 5%, 10%) Lu alloys were manufactured via mechanical alloying for 20 h and a spark plasma sintering process at 1,873 K for 2 min. The effects of Lu doping on the microstructure and performance of W were investigated using various techniques. For irradiation performance analysis, thermal desorption spectroscopy (TDS) measurements were performed from room temperature to 1,000 K via infrared irradiation with a heating rate of 1 K/s after implantations of He⁺ and D⁺ ions. TDS measurements were conducted to investigate D retention behavior. Microhardness was dramatically enhanced, and the density initially increased and then decreased with Lu content. The D retention performance followed the same trend as the density. Second-phase particles identified as Lu₂O₃ particles were completely distributed over the W grain boundaries and generated an effective grain refinement. Transgranular and intergranular fracture modes were observed on the fracture surface of the sintered W-Lu samples, indicating some improvement of strength and toughness. The amount and distribution of Lu substantially affected the properties of W. Among the investigated alloy compositions, W-5%Lu exhibited the best overall performance.

Ultra-fine tungsten carbide (WC) powder refers to WC powders with a particle size between 100 to 500 nm. Researchers have improved the comprehensive properties of WC-based cemented carbides by preparing ultra-fine WC powders. Because of the preparation and application of nano-scale WC powders, ultrafine-grain cemented carbides with excellent hardness and wear resistance have been successfully produced. In this paper, the preparation methods of ultra-fine WC powder are divided into solid-phase, liquid-phase, and vapor-phase methods according to the state of the raw materials (i.e., the W or C source). The liquid-phase methods could realize the preparation of WC at the temperature between 500 - 800 °C. The purity of WC prepared by vapor-phase method is the highest. The solid-phase reduction carbonization method has potential industrial application.