Herein, the evolution of reduction process of ultrafine tungsten powder in industrial conditions was investigated. The transition process of morphology and composition was examined via SEM, XRD, and calcination experiments. The results show that the reduction sequence of WO 2.9 was WO 2.9 → WO 2.72 → WO 2 → W on the surface, but WO 2.9 → WO 2 → W inside the oxide particles. With the aid of chemical vapor transport of WO x (OH) y , surface morphology transformed into rod-like, star-shaped cracking, floret, irregularly fibrous structure, and finally, spherical tungsten particles.

中文翻译：

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氧化钨通过氢气还原超细钨粉的过程演变

在此，研究了工业条件下超细钨粉还原过程的演变。通过SEM、XRD和煅烧实验研究了形貌和组成的转变过程。结果表明，WO 2.9 的还原顺序为表面WO 2.9 → WO 2.72 → WO 2 → W，而在氧化物颗粒内部为WO 2.9 → WO 2 → W。借助WO x (OH) y 的化学气相传输，表面形态转变为棒状、星形裂纹、小花、不规则纤维结构，最终形成球形钨颗粒。