Cai Junyu, Ma Songhua, Yi Wenbin, Wang Jieping
School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, China.
Adv Sci (Weinh). 2024 Oct;11(39):e2405487. doi: 10.1002/advs.202405487. Epub 2024 Aug 13.
Current additive manufacturing (AM) techniques for tungsten, such as powder bed fusion and directed energy deposition, often generate parts with rough surfaces. Vat photopolymerization presents a promising alternative for fabricating tungsten structures with high shape fidelity and low surface roughness. However, existing vat photopolymerization approaches suffer from surface defects and low final density, leading to compromised mechanical properties. Therefore, achieving high-density tungsten structures using vat photopolymerization remains a crucial challenge. This work presents a straightforward and reliable method for fabricating complex, micro-architected tungsten structures with superior density and hardness. The approach utilizes a water-based photoresin with exceptional tungsten ion loading capacity. The photoresin is then patterned using digital light processing (DLP) to create tungsten-laden precursors. A three-step debinding and sintering process subsequently achieves 3D tungsten structures with dense surface morphology and minimal internal defects. The microstructures achieve a minimum feature size of 35 µm, a low surface roughness of 2.86 µm, and demonstrate exceptional mechanical properties. This new method for structuring tungsten opens doors to a broad range of applications, including micromachining, collimators, detectors, and metamaterials.
当前用于钨的增材制造（AM）技术，如粉末床熔融和定向能量沉积，通常会生成表面粗糙的零件。光固化3D打印为制造具有高形状保真度和低表面粗糙度的钨结构提供了一种有前景的替代方法。然而，现有的光固化3D打印方法存在表面缺陷和最终密度低的问题，导致机械性能受损。因此，使用光固化3D打印实现高密度钨结构仍然是一个关键挑战。这项工作提出了一种直接且可靠的方法，用于制造具有卓越密度和硬度的复杂微结构钨结构。该方法利用了一种具有出色钨离子负载能力的水基光致抗蚀剂。然后使用数字光处理（DLP）对光致抗蚀剂进行图案化，以创建含钨前驱体。随后的三步脱脂和烧结工艺实现了具有致密表面形态和最小内部缺陷的3D钨结构。这些微结构的最小特征尺寸为35微米，表面粗糙度低至2.86微米，并展现出卓越的机械性能。这种新的钨结构化方法为包括微加工、准直器、探测器和超材料在内的广泛应用打开了大门。
