Fine-grained Mo alloys doped with uniformly distributed nanoscale Y₂O₃ particles were successfully prepared by employing two powerful strategies: fabricating high-quality precursor powders using hydrothermal synthesis and subsequent powder consolidation by spark plasma sintering (SPS) technique. In this study, the effect of hydrothermal variables on the morphology and existent form of yttrium and Mo was systematically studied, and the refinement mechanism of reduced mixing powders and the densification under the different sintering parameters were investigated. The results show that spherical Y₂(CO₃)₃·2H₂O gradually replaced Y(OH)CO₃ owing to the increased concentration of hydrogen bonds and CO₃²⁻ at excess alcohol and urea, and lamellar (NH₄)₂Mo₄O₁₃ developed into large pillar-shaped h-MoO₃ with decreasing pH. Due to the low calculated lattice mismatch degree of Mo/Y₂O₃ interfaces ~10.9%, Y₂O₃ particles further refined and homogenized the reduced mixing powders as heterogeneous nucleating sites. After sintering at 1700 °C for 5 min with a heating rate of 100 °C/min, Mo-Y₂O₃ alloys possessed fine grains of 1.80 ± 0.17 μm, a high density of 98.18% and the high indentation hardness of 314.77 ± 26.12 HV_0.3 and 4.82 ± 0.53 GPa H_IT. The Y₂O₃ particles were uniformly distributed in the Mo matrix, and semi-coherent with Mo lattice, with the orientation relationships as follows: (010)_Y2O3//(011)_Mo, (01-1)_Y2O3//(020)_Mo, and [100]_Y2O3//[100]_Mo.

通过采用两种有效的策略成功制备了掺杂有均匀分布的纳米级Y ₂ O ₃颗粒的细晶粒Mo合金：使用水热合成法制备高质量的前驱体粉末，以及随后通过火花等离子体烧结（SPS）技术进行粉末固结。本研究系统地研究了水热变量对钇和钼的形态和存在形式的影响，并研究了不同烧结参数下混合粉末的还原细化和致密化。结果表明，球形Y ₂（CO ₃）₃ ·2H ₂ O逐渐取代了Y（OH）CO _3。由于过量的醇和尿素中氢键和CO ₃ ^2-的浓度增加，层状（NH ₄）₂ Mo ₄ O ₁₃逐渐形成大的柱状h-MoO ₃，pH降低。由于Mo / Y ₂ O ₃界面的计算出的晶格失配度较低，约为10.9％，Y ₂ O ₃颗粒可进一步精制和均质化还原后的混合粉末，成为异质形核位点。在1700°C下以100°C / min的加热速率烧结5分钟后，Mo-Y ₂ O ₃合金具有1.80±0.17μm的细晶粒，98.18％的高密度和314.77±26.12 HV _0.3和4.82±0.53 GPa H _IT的高压痕硬度。Y ₂ O ₃颗粒均匀地分布在Mo基体中，并与Mo晶格半相干，其取向关系如下：（010）_Y2O3 //（011）_Mo，（01-1）_Y2O3 //（020） ）_Mo和[100] _Y2O3 // [100] _Mo。