Enabling high-performance 3D printing of Al powder by decorating with high laser absorbing Co phase
Enabling high-performance 3D printing of Al powder by decorating with high laser absorbing Co phase
复制标题
通过高激光吸收 Co 相修饰实现 Al 粉末的高性能 3D 打印
DOI：
10.1016/j.addma.2019.101012
复制
发表时间：
2020-03-01
影响因子：
11
通讯作者：
Zhu, Qingshan
中科院分区：
文献类型：
--
作者：
Geng, Kang;Yang, Yafeng;Zhu, Qingshan
具有高激光反射率的纯铝本质上与激光粉床熔合是不相容的。大量未熔化颗粒的保留导致印刷纯铝零件的几何质量和力学性能较差。在本研究中，我们提出在Al粉末表面用少量高激光吸收的Co纳米颗粒修饰Al，以降低激光反射率，提高印刷适性。实验结果证明了该方法的有效性。Co的均匀分散使粉末表面的化学成分发生了轻微的变化，使粉末表面变得粗糙。这种方法完全熔化了颗粒并消除了内部孔隙，从而有利于调整几何尺寸。此外，Co的引入通过与Al基体形成共格界面关系的第二相Al9Co2的分散提供了固溶强化和沉淀硬化。在最佳含量为0.5 wt.%时，打印铝零件的拉伸性能可与商用中等强度铝合金相媲美。
Pure Al with high laser reflectivity is essentially incompatible with laser powder bed fusion. The retention of a large number of unmelted particles leads to inferior geometrical quality and mechanical properties of printed pure Al parts. In the present study, we propose decorating Al with a small amount of high laser absorbing Co nanoparticles on the surface of Al powders to reduce laser reflectivity and improve printability. The experimental results confirmed that the approach was very effective. The near homogenous dispersion of Co slightly modified the surface chemical composition and roughened the powder surface. This approach completely melted the particles and eliminated the internal pores, thereby favorably tuning the geometrical dimensions. Additionally, the introduction of Co provided solid solution strengthening and precipitation hardening via dispersion of second-phase Al9Co2 with a coherent interfacial relationship with the Al matrix. The tensile properties of printed Al parts were comparable to commercial medium-strength Al alloys at an optimal Cocontent of 0.5 wt.%.