Abstract Over the last three decades, a variety of additive manufacturing techniques have gradually gained maturity and will potentially play an important role in future manufacturing industries. Among them, direct ink writing has attracted significant attention from both material and tissue engineering areas, where the colloidal ink is extruded and dispensed according to a pre-designed path, usually in the X-Y plane with suitable increments in the Z direction. Undoubtedly, this way of disassembling geometries, simple or complex, can facilitate most of the printing process. However, for one extreme case, i.e. pillar arrays, the size resolution can deviate from both nozzle and design if the common way of slicing and additive manufacturing is used. Therefore, a different printing path is required – directly depositing pillars in a converse gravitational direction. This paper gives multiple examples of printing viscoelastic colloidal ceramic and metal inks uniaxially and periodically into free-standing and height-adjustable pillar arrays. It is expected to inspire the additive manufacturing community that more versatile degrees of freedom and complex printing paths, not confined within only complex shapes, can be achieved by ink-based 3D printing.

中文翻译：

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垂直 3D 打印：直接墨水书写独立柱阵列

摘要 在过去的三十年中，各种增材制造技术逐渐成熟，并可能在未来的制造业中发挥重要作用。其中，直接墨水书写引起了材料和组织工程领域的极大关注，其中胶体墨水根据预先设计的路径挤出和分配，通常在 XY 平面上，在 Z 方向上有适当的增量。毫无疑问，这种分解几何图形的方式，无论简单还是复杂，都可以促进大部分印刷过程。然而，对于一种极端情况，即柱状阵列，如果使用常见的切片和增材制造方式，尺寸分辨率可能会偏离喷嘴和设计。所以，需要不同的打印路径——直接在相反的重力方向上沉积柱子。本文给出了多个示例，将粘弹性胶体陶瓷和金属油墨单轴周期性地打印到独立且高度可调的柱阵列中。预计通过基于墨水的 3D 打印可以实现更多功能的自由度和复杂的打印路径，而不仅限于复杂的形状，这有望激发增材制造社区的灵感。