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    Method to produce a transition metal carbide from a partially reduced transition metal compound
    21.
    发明授权
    Method to produce a transition metal carbide from a partially reduced transition metal compound 失效
    从部分还原的过渡金属化合物制备过渡金属碳化物的方法

    公开(公告)号：US5942204A

    公开(公告)日：1999-08-24

    申请号：US967965

    申请日：1997-11-12

    申请人： Stephen D. Dunmead ,  Hobart A. Barker ,  John P. Henley ,  Pat J. DeLuca ,  Tom J. Bunnelle ,  Joe F. Repman ,  Daniel F. Carroll ,  Stephen A. Anderson

    发明人： Stephen D. Dunmead ,  Hobart A. Barker ,  John P. Henley ,  Pat J. DeLuca ,  Tom J. Bunnelle ,  Joe F. Repman ,  Daniel F. Carroll ,  Stephen A. Anderson

    IPC分类号： C01B31/30 ,  C01B31/34

    CPC分类号： C01B31/303 ,  C01B31/305 ,  C01B31/34 ,  C01P2006/12 ,  C01P2006/80

    摘要： A transition metal carbide (e.g., WC) is prepared by the following steps. A carbon-precursor mixture is formed by mixing a precursor comprised of (i) a transition metal oxide (e.g., WO.sub.x) and (ii) a material selected from the group consisting of: a transition metal (e.g., W); a transition metal carbide (e.g., WC) and a substoichiometric carbide (W.sub.2 C), in the presence of a source of carbon (e.g., carbon black) in an amount sufficient to form a reduced mixture comprised of the transition metal carbide and substoichiometric transition metal carbide, wherein the amount of the transition metal oxide and transition metal is essentially zero in said reduced mixture. The carbon-precursor mixture is heated in a reducing atmosphere (e.g., 5 percent hydrogen in argon) to a reducing temperature and for a time sufficient to produce the reduced mixture. The reduced mixture is milled in the presence of a source of carbon in an amount sufficient to carburize the substoichiometric transition metal carbide to form the transition metal upon heating in a reducing atmosphere. Finally, the milled reduced mixture is heated in a reducing atmosphere to a carburizing temperature that is greater than the reducing temperature for a time sufficient to carburize the substoichiometric transition metal carbide to form the transition metal carbide of this invention (e.g., WC).

    摘要翻译： 通过以下步骤制备过渡金属碳化物（例如WC）。 通过混合由（i）过渡金属氧化物（例如WOx）和（ii）选自以下的材料组成的前体形成碳前体混合物：过渡金属（例如W）; 在碳源（例如炭黑）存在下，过渡金属碳化物（例如WC）和亚化学计量碳化物（W2C）的量足以形成由过渡金属碳化物和亚化学计量过渡金属组成的还原混合物 碳化物，其中过渡金属氧化物和过渡金属的量在所述还原的混合物中基本为零。 将碳前体混合物在还原气氛（例如氩气中的5％氢气）中加热至还原温度并持续足以产生还原混合物的时间。 将还原的混合物在碳源存在下研磨，其量足以使亚化学计量过渡金属碳化物渗碳以在还原气氛中加热时形成过渡金属。 最后，将研磨后的还原混合物在还原气氛中加热至大于还原温度的渗碳温度足以使亚化学计量过渡金属碳化物渗碳形成本发明的过渡金属碳化物（例如WC）的时间。

    Method of making metallic carbide powders
    22.
    发明授权
    Method of making metallic carbide powders 失效
    制造金属碳化物粉末的方法

    公开(公告)号：US5567662A

    公开(公告)日：1996-10-22

    申请号：US196928

    申请日：1994-02-15

    申请人： Stephen D. Dunmead ,  David D. Mossner

    发明人： Stephen D. Dunmead ,  David D. Mossner

    IPC分类号： B22F9/30 ,  C01B31/30 ,  C01B31/34 ,  C04B35/56

    CPC分类号： C01B31/301 ,  C01B31/30 ,  C01B31/34 ,  C01P2004/62 ,  C01P2006/80

    摘要： A method of making metallic carbide powders includes heating a non-static solid reactant mixture of a metal oxide and a source of carbon to a first elevated temperature which is sufficient to cause at least partial carburization of the mixture. The heating is performed in a non-reducing atmosphere having a total pressure of at least one atmosphere for a sufficient time to form a partially-carburized mixture. The source of carbon is employed at a level which is less than the stoichiometric amount needed to produce the metallic carbide. The method may further include admixing a sufficient level of a source of carbon to the partially-carburized mixture to form an adjusted mixture having a total carbon content of the stoichiometric amount needed to make the metallic carbide and carburizing the adjusted mixture in a hydrogen-containing atmosphere at a second elevated temperature which is sufficient to cause the adjusted mixture to form the metallic carbide having a particle size of less than 0.2 micrometers in diameter.

    摘要翻译： 制备金属碳化物粉末的方法包括将金属氧化物和碳源的非静态固体反应物混合物加热至足以引起混合物至少部分渗碳的第一升高温度。 加热在具有至少一个气氛的总压力的非还原气氛中进行足够的时间以形成部分渗碳的混合物。 碳源的使用量低于生产金属碳化物所需的化学计量量。 该方法可以进一步包括将足够水平的碳源混合到部分渗碳的混合物中以形成调节的混合物，其具有制备金属碳化物所需的化学计量量的总碳含量并将调节的混合物渗碳在含氢 气氛在足以使经调整的混合物形成粒径小于0.2微米直径的金属碳化物的第二升高温度下进行。