W@WC/Cu复合材料的结构调控及其对耐电弧烧蚀特性的影响

Aiming to the challenge of traditional tungsten-copper pseudo-alloy is difficult to deal with the service environment increasingly stringent of military and important people's livelihood project. The W@WC coating structures with half coated and ornament coated were formed on the surface of tungsten skeleton using vacuum pulse carburizing process and in situ synthesis technology, then the W@WC/Cu composites were fabricated through infiltration process. The purpose is to improve the arc erosion resistance, high temperature strength and high temperature wear resistance of W@WC/Cu composites on the basis of reduce the conductive properties as little as possible. In the processes of vacuum pulse carburizing, in situ synthesis and infiltration sintering, the macro regularity and the micro mechanism of absorption and diffusion for gas phase carbon source in the tungsten skeleton will be detailed study. The relationship between carburizing parameters and area, thickness of coating structure in tungsten skeleton will be established. The influence regulation of different coating structure on the arc erosion resistance, high temperature performances and conductive properties will be discussed, and the reasonable matching between the arc erosion resistance, high temperature strength, high temperature wear resistance and electric conductivity will be realized. Finally, the preparation technology prototype of W@WC/Cu composites with good performance will be established. The results provides a new thought and method for improving the surface performance of WCu composites, it has important academic value and application prospect.

针对传统钨铜假合金难以应对军工和重要民生工程日益苛刻的服役环境的挑战，本项目拟采用真空脉冲渗碳工艺和原位自生增强技术，在钨骨架表层形成半包覆或点缀包覆W@WC包覆结构，然后熔渗铜形成W@WC/Cu复合材料，旨在不降低或尽量少降低复合材料传导性能的基础上，提高W@WC/Cu复合材料表层的耐电弧烧蚀特性、高温强度和高温耐磨性。重点研究真空脉冲渗碳、原位自生增强以及烧结熔渗过程中，气相碳源在钨骨架中吸附、扩散的宏观规律及微观机理，建立渗碳参数与钨骨架包覆层包覆面积、厚度的关系，阐明W@WC不同包覆形式对复合材料耐电弧烧蚀特性、高温性能和传导性能的影响规律，实现耐电弧烧蚀特性、高温强度、高温耐磨性与导电性能的合理匹配，形成高性能W@WC/Cu复合材料的制备技术原型。研究结果为WCu复合材料表面性能的改善提供了一种新的思路和方法，具有重要的学术价值及应用前景。

本项目针对传统钨铜假合金难以应对军工和重要民生工程日益苛刻的服役环境的挑战，采用真空脉冲渗碳工艺和原位自生增强技术，在钨骨架表层形成半包覆或点缀包覆W@WC包覆结构，然后熔渗铜形成W@WC/Cu复合材料，在不降低或尽量少降低复合材料传导性能的基础上，提高W@WC/Cu复合材料表层的耐电弧烧蚀特性、高温强度和高温耐磨性。首先，通过原始钨颗粒粒径大小、钨骨架致密度等参数的变化，研究了钨骨架特性参数对渗碳层厚度、原位生成WC陶瓷颗粒分布及含量的影响及其对复合材料表层硬度、电导率、强度及耐磨性的影响规律；其次，通过调整真空脉冲渗碳温度和渗碳时间，探索了渗碳温度和渗碳时间对W@WC/Cu复合材料渗碳层厚度、原位生成WC陶瓷颗粒分布及含量的影响及其对复合材料表层硬度、电导率、强度、耐磨性及耐电弧烧蚀性能的影响规律；再次，揭示了真空脉冲渗碳过程气相碳源在钨骨架中吸附、扩散的宏观规律及微观机理，建立了渗碳参数与钨骨架包覆层包覆面积、厚度的关系；最后，揭示了W@WC包覆结构的形成机理及调控机制，阐明了W@WC半包覆、点缀包覆等不同包覆形式对复合材料耐电弧烧蚀特性、高温性能和传导性能的影响规律，实现了耐电弧烧蚀特性、高温强度、高温耐磨性与导电性能合理匹配的高性能W@WC/Cu复合材料的可控制备。研究结果为WCu复合材料表面性能的改善提供了一种新的思路和方法，具有重要的学术价值及应用前景。