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用超声喷雾制备的（Ｗ，Ｎｉ，Ｆｅ，Ｖ）系纳米级复合氧化物粉末，在管式还原炉内以不同流量的液化石油气还原碳化，制备含Ｖ的超细晶粒硬质合金粉末。用化学分析、Ｘ射线衍射（ＸＲＤ）和透射电镜（ＴＥＭ）确定粉末的成分、物相组成及粉末颗粒形貌和粒度范围。将合金粉末热压成合金试样，观察Ｖ元素的分布及对ＷＣ晶粒长大的抑制作用。结果表明，１２０ｍＬ·ｍｉｎ(－１)的液化气流量，虽可使复合氧化物转变成ＷＣ，ＶＣ，Ｎｉ，Ｆｅ相，但会造成合金粉中含有很高的游离Ｃ。当液化气流量为４３ｍＬ．ｍｉｎ(－ｌ)时，合金粉的物相组成及游离Ｃ含量全部达到要求。电镜观察证实，Ｖ元素可以抑制ＷＣ晶粒长大，并主要分布在粘结相中
(W, Ni, Fe, V) nanoscale composite oxide powders prepared by ultrasonic spray were reduced carbonized with liquefied petroleum gas of different flow rates in a tubular reduction furnace to prepare V-containing ultrafine grained cemented carbide powders . The chemical composition, X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to determine the powder composition, phase composition and powder particle morphology and particle size range. The alloy powders were hot pressed into alloy samples to observe the distribution of V elements and inhibit the growth of WC grains. The results show that the flow rate of liquefied gas of 120mL · min -1 can change the composite oxide into WC, VC, Ni and Fe phases, but it will cause high free C content in the alloy powders. When the liquefied gas flow rate is 43mL. min (-l), the phase composition of the alloy powder and free C content all meet the requirements. Electron microscopy confirmed that the V element can inhibit WC grain growth, and mainly distributed in the binder phase