Mechanical Engineering , Polytechnique Montreal , C.P. 6079, succ. Centre-Ville , Montreal , Québec H3C 3A7 , Canada.
Metallurgy Engineering , Polytechnique Montreal , C.P. 6079, succ. Centre-Ville , Montreal , Québec H3C 3A7 , Canada.
ACS Appl Mater Interfaces. 2019 Feb 27;11(8):8499-8506. doi: 10.1021/acsami.8b19986. Epub 2019 Feb 12.
Direct ink writing (DIW) combined with post-deposition thermal treatments is a safe, cheap, and accessible additive manufacturing (AM) method for the creation of metallic structures. Single-material DIW enables the creation of complex metallic 3D structures featuring overhangs, lengthy bridges, or enclosed hollows, but requires the printing supporting structures. However, the support printed from the same material becomes inseparable from the building structure after the thermal treatment. Here, a multi-material DIW method is developed to fabricate complex three-dimensional (3D) steel structures by creating a removable support printed from a lower melting temperature metal (i.e., copper) or a ceramic (i.e., alumina). The lower melting temperature metal completely infiltrates the porous steel structures for a hybrid configuration, while the ceramic offers a brittle support that can be easily removed. The influence of the support materials on the steel structure properties is investigated by characterizing the dimensional shrinkage, surface roughness, filament porosity, electrical conductivity, and tensile properties. The hybrid configuration (i.e., copper infiltrated steel structures) improves the electrical conductivity of the fabricated steel structure by 400% and the mechanical stiffness by 34%. The alumina support is physically and chemically stable during the thermal treatment, bringing no significant contamination to the steel structure.
直写（DIW）结合后沉积热处理是一种安全、廉价且易于使用的增材制造（AM）方法，可用于制造金属结构。单一材料的 DIW 可用于创建具有悬垂、长桥或封闭空心的复杂金属 3D 结构，但需要打印支撑结构。然而，经过热处理后，与建筑结构相同的材料打印的支撑结构无法分离。在这里，开发了一种多材料 DIW 方法，通过创建由低熔点金属（即铜）或陶瓷（即氧化铝）制成的可移除支撑来制造复杂的三维（3D）钢结构。低熔点金属完全渗透多孔钢结构，形成混合配置，而陶瓷则提供了一种易碎的支撑，易于去除。通过对尺寸收缩、表面粗糙度、丝材孔隙率、导电性和拉伸性能进行表征，研究了支撑材料对钢结构性能的影响。混合配置（即铜渗透的钢结构）使所制造的钢结构的导电性提高了 400%，机械刚度提高了 34%。氧化铝支撑在热处理过程中物理和化学稳定，不会对钢结构造成明显的污染。
