(南京航空航天大学 材料科学与技术学院, 南京 210016)
摘 要: 对不同CuP含量的多组分铜基金属粉末（Cu-CuSn-CuP）进行了选区激光烧结实验。 利用X射线衍射和扫描电镜研究了添加元素P对烧结致密度及显微组织的影响。 研究表明： P元素能在烧结过程中充当脱氧剂而与Cu反应生成CuPO3； 但当P过量时, 则会因熔体过热倾向明显而加剧氧化； 适量增加P元素能改善烧结件层间结合性； 而P元素过量则会因生成过多磷渣而降低润湿性及致密度； P元素亦能充当稀释剂而降低熔体粘度及表面张力, 从而改善烧结致密度及组织均匀性；但若P元素过量时, 则会因熔体粘度过低而导致球化现象。 实验结果证实, 该组铜基金属粉末体系中CuP的最佳含量为15%。
关键字: 铜基金属粉末； 添加剂； 选区激光烧结； 液相烧结
（College of Materials Science and Technology,
Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China）
Abstract: The selective laser sintering experiment of the multi-component copper-based metal powder systems (Cu-CuSn-CuP) with different CuP contents was carried out. The effects of the P addition on the densification and the resultant microstructural features of the laser sintered powder were investigated by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results show that P can act as deoxidizer to react with Cu and form CuPO3. However, excessive P addition results in a larger degree of superheat of the melt, hence aggravating the oxidation. The bonding coherence between the sintered layers increases with the increase of the content of phosphorus. However, at a large amount of P, the solid-liquid wettability and the resultant densification decrease due to the excessive formation of P slag. Element P can also act as a fluxing agent to decrease the surface tension and viscosity of the melt, thereby improve the sintered densification and the microstructural homogeneity. Whereas, with excessive P addition, an extremely low melt viscosity causes balling phenomena. The results show that the optimal mass fraction of the CuP in the powder system is 15%.
Key words: copper-based metal powder; additive; selective laser sintering; liquid phase sintering
