钨渗铜复合材料致密化机理研究

Investigation on Densification Mechanism of Copper Infiltrated Tungsten Composites

以粗细钨粉和铜丝为原料,采用粉末冶金工艺制备钨骨架,随后通过液态熔渗铜的方法制备低铜含量(质量分数低于10%)的钨渗铜复合材料。利用电子天平、金相显微镜和扫描电镜分析材料的致密度及显微组织,对材料在制备过程中的致密化机理进行探讨。结果表明:钨渗铜复合材料熔渗过程的驱动力既有毛细管力又有晶界扩散作用,熔渗路径可用根系模型来阐释;在钨骨架中加入Ni等诱导金属可强化熔渗过程;低铜含量的致密钨渗铜复合材料需制备高致密度且具有联通晶界或孔隙的钨骨架。

Using coarse and fine tungsten powder and copper wire as raw materials,tungsten skeletons were prepared by powder metallurgy,and then copper infiltrated tungsten composites with low copper content(mass fraction lower than 10%) were produced by copper liquid infiltration.The density and microstructure of the composites were analyzed by electronic balance,metallographic microscope and scanning electron microscope,and the densification mechanism of the composites in the infiltration process was discussed.The results show that both capillary force and grain boundary diffusion are the driving force in the infiltration process of tungsten infiltrated copper composites,and the infiltration path can be explained by root system model.Adding inducible metals such as Ni to the tungsten skeleton can strengthen the infiltration process.To prepare dense copper infiltrated tungsten composites with low copper content,tungsten skeletons with high density and interconnected grain boundaries or pores are required.