含碳雾滴燃烧-碳氢协同还原制备纳米W-Cu复合粉末的反应机制研究

纳米W-Cu复合粉末可有效降低烧结温度并提高烧结致密度，是制造高性能W-Cu部件的主要原料。然而，制备纳米W-Cu复合粉末存在W晶粒长大和W-Cu颗粒团聚的问题。本项目基于W晶粒生长规律和W-Cu颗粒分散原理，提出含碳雾滴燃烧-碳氢协同还原制备纳米W-Cu复合粉末的新方法。首先，使含碳雾滴在运动中发生自蔓延燃烧反应，制备出含碳前驱物；然后，将前驱物进行碳氢协同还原反应，得到纳米W-Cu复合粉末。系统研究含碳雾滴的特性和运动燃烧行为对前驱物性能的影响规律；深入研究前驱物碳氢协同还原制备纳米W-Cu复合粉末的反应过程及其机理，揭示W晶粒细化规律和W-Cu颗粒均匀分散调控机制，解决W晶粒长大和W-Cu颗粒团聚的难题，构建含碳雾滴燃烧-碳氢协同还原制备纳米W-Cu复合粉末的基本理论。该研究为纳米W-Cu复合粉末的工业化制备奠定理论和技术基础，并将为制备其它高性能粉末冶金材料提供思路和借鉴。

Nano W-Cu composite powder can reduce sintering temperature effectively and increase sintering density, so that it is a main raw material for the manufacture of high-performance W-Cu parts. W grain growth and W-Cu particle agglomeration are the key problems in obstruction preparation of nano W-Cu composite powder. Based on growth regulation of W grains and dispersion principle of W-Cu particles, this project intends to explore a new approach for preparing nano W-Cu composite powder by combining carbon-containing droplet combustion and carbon-hydrogen co-reduction methods. First, an uniform precursor of carbon-containing was synthesized by self-propagating combustion reaction of carbon-containing droplets in moving, and then the nano W-Cu composite powder was obtained by means of carbon-hydrogen co-reduction of this precursor. The effect laws of the characteristics and combustion behavior in moving for carbon-containing droplets on the properties of precursor will studied systematically, and the reaction process and its mechanism for preparing nano W-Cu composite powder by means of carbon-hydrogen co-reduction of this precursor will be investigated in detail. Based above research results, the refinement rule of W grains and the regulation mechanism of uniform dispersion of W-Cu particles will be revealed, the problems of W grain growth and W-Cu particle agglomeration will be solved, and the basic theory of preparing nano W-Cu composite powder by carbon-containing droplet combustion and carbon-hydrogen co-reduction methods will be structured. This project not only is expected to provide the theoretical and technique foundations for industrialized preparation of nano W-Cu composite powder, but also will provide a reference for preparing other high-performance powder metallurgy materials.