(南京航空航天大學(xué) 材料科學(xué)與技術(shù)學(xué)院, 南京 210016)
摘 要: 對(duì)不同CuP含量的多組分銅基金屬粉末（Cu-CuSn-CuP）進(jìn)行了選區(qū)激光燒結(jié)實(shí)驗(yàn)。 利用X射線衍射和掃描電鏡研究了添加元素P對(duì)燒結(jié)致密度及顯微組織的影響。 研究表明： P元素能在燒結(jié)過(guò)程中充當(dāng)脫氧劑而與Cu反應(yīng)生成CuPO3； 但當(dāng)P過(guò)量時(shí), 則會(huì)因熔體過(guò)熱傾向明顯而加劇氧化； 適量增加P元素能改善燒結(jié)件層間結(jié)合性； 而P元素過(guò)量則會(huì)因生成過(guò)多磷渣而降低潤(rùn)濕性及致密度； P元素亦能充當(dāng)稀釋劑而降低熔體粘度及表面張力, 從而改善燒結(jié)致密度及組織均勻性；但若P元素過(guò)量時(shí), 則會(huì)因熔體粘度過(guò)低而導(dǎo)致球化現(xiàn)象。 實(shí)驗(yàn)結(jié)果證實(shí), 該組銅基金屬粉末體系中CuP的最佳含量為15%。
關(guān)鍵字: 銅基金屬粉末； 添加劑； 選區(qū)激光燒結(jié)； 液相燒結(jié)
（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
