Synthesis, performances and characterization of fine-grained W-Y-Ti composites via organic chemical method

Nano powder plays a key role in preparing high performance tungsten-based materials. It is necessary to synthesize powder with uniform element distribution, low impurity content, and fine particles for preparing higher performance tungsten-based materials with more uniform microstructure, with smaller grain size and higher densification. However, it is difficult to synthesize uniform oxide/carbide reinforced tungsten matrix composite powders with specific structure by traditional powder metallurgy method. In this manuscript, nano W-Y-Ti powders with core-shell structure were synthesized by organic chemical method. The average grain size of W-Y-Ti is 33.33 nm, which indicates the powder refinement is 1 order of magnitude compared with other methods. Moreover, due to the difference of Y 3+ and Ti 4+ , the Y phase tends to form core in W particle and the Ti phase tends to form shell around W particle in these powders synthesized by organic chemical method. This powder structure is conducive to in-situ dispersion of the reinforced phase during sintering and significantly improves the interface properties of the reinforced phase /W matrix phase. The W-Y-Ti composite prepared by SPS shows fine grain size (750 nm) and uniform distribution (Y 2 O 3 is distributed within the W grain, while Ti is distributed at the grain boundaries). It means the microstructure of the powder can be inherited to the bulk materials, which can improve the performance of these composites. This manuscript provides ideas and data basis for the synthesis and preparation of high-strength, tough and high-performance W-based composite materials.