Crespi Angela Elisa, Nordet Guillaume, Peyre Patrice, Ballage Charles, Hugon Marie-Christine, Chapon Patrick, Minea Tiberiu
Laboratoire de Physique des Gaz et Plasmas, LPGP, Université Paris-Saclay, CNRS, F-91405 Orsay Cedex, France.
Groupe de Recherches sur l'Energétique de Milieux Ionisé GREMI, Université d'Orléans, CNRS UMR7344 14 Rue d'Issoudun BP6744, 45067 Orléans Cedex 2, France.
Materials (Basel). 2023 Mar 20;16(6):2460. doi: 10.3390/ma16062460.
Thin and ultrathin carbon films reduce the laser energy required for copper powder fusion in selective laser melting (SLM). The low absorption of infrared (IR) radiation and its excellent thermal conductivity leads to an intricate combination of processing parameters to obtain high-quality printed parts in SLM. Two carbon-based sacrificial thin films were deposited onto copper to facilitate light absorption into the copper substrates. Graphite-like (3.5 µm) and ultra-thin (25 nm) amorphous carbon films were deposited by aerosol spraying and direct current magnetron sputtering, respectively. The melting was analyzed for several IR (1.06 µm) laser powers in order to observe the coating influence on the energy absorption. Scanning electron microscopy showed the topography and cross-section of the thermally affected area, electron backscatter diffraction provided the surface chemical composition of the films, and glow-discharge optical emission spectroscopy (GDOES) allowed the tracking of the in-deep chemical composition of the 3D printed parts using carbon film-covered copper. Ultra-thin films of a few tens of nanometers could reduce fusion energy by about 40%, enhanced by interferences phenomena. Despite the lower energy required, the melting maintained good quality and high wettability when using top carbon coatings. A copper part was SLM printed and associated with 25 nm of carbon deposition between two copper layers. The chemical composition analysis demonstrated that the carbon was intrinsically removed during the fusion process, preserving the high purity of the copper part.
薄和超薄碳膜降低了选择性激光熔化（SLM）中铜粉熔化所需的激光能量。红外（IR）辐射的低吸收率及其优异的热导率导致在SLM中获得高质量打印部件所需的加工参数组合复杂。将两种碳基牺牲薄膜沉积在铜上，以促进光吸收到铜基板中。类石墨（3.5 µm）和超薄（25 nm）非晶碳膜分别通过气溶胶喷涂和直流磁控溅射沉积。分析了几种红外（1.06 µm）激光功率下的熔化情况，以观察涂层对能量吸收的影响。扫描电子显微镜显示了热影响区域的形貌和横截面，电子背散射衍射提供了薄膜的表面化学成分，辉光放电光发射光谱（GDOES）允许使用碳膜覆盖的铜跟踪3D打印部件的深度化学成分。几十纳米的超薄薄膜可将熔化能量降低约40%，这是由干涉现象增强的。尽管所需能量较低，但使用顶部碳涂层时，熔化仍保持良好的质量和高润湿性。通过SLM打印了一个铜部件，并在两层铜之间沉积了25 nm的碳。化学成分分析表明，碳在熔化过程中被固有去除，保持了铜部件的高纯度。
