钒元素对纳米钨粉在高温加热过程中颗粒长大的抑制作用

采用V（NO3）5为抑制剂，分别加入到溶胶-凝胶反应前的钨酸铵溶液中及溶胶反应后的凝胶体中，制备含V前躯体粉，并经二阶段低温还原法制备纳米W粉。采用XRD表征了纳米W粉经650—950℃保温30min处理过程物相的组成及相的变化，用FESEM观察分析了纳米W粉的颗粒形貌。用定量金相测定了不同处理温度下的颗粒尺寸。初步探讨了以V（NO3）5为抑制剂对纳米W粉在还原阶段及加热保温阶段长大的抑制效果。结果表明，V（NO3）5作为抑制剂的加入可有效抑制纳米W粉在还原阶段及加热保温阶段的长大。

Inhibited Effect of Vanadium on the Grain Growth of Tungsten Nanopowder during Reducing and Heating Insulation

The precursor powders containing vanadium were prepared by sol-gel method,respectively adding V(NO3)5 solution as inhibitor into ammonium tungstate solution as the reactant of sol-gel and the gel. Subsequently,the precursors were reduced into tungsten nanopowder by two-step reductions. The phase composition and transformation were characterized by XRD,The particle size and morphology were characterized by FESEM,metallographical quantification and SAXS. And the effect of the inhibitor on tungsten nanopowder was investigated,and the mechanism of inhibiting grain growth was discussed. The results indicate that the addition of V(NO3)5 as a inhibitor effectively inhibits the grain growth of tungsten nanopowder during reducing and heating insulation.