Continuous 3D printing of metal structures using ultrafast mask video projection initiated vat photopolymerization

Abstract

Additive manufacturing (AM) has recently emerged as the go-to technology for producing high-quality metal components to address cutting-edge research and industrial challenges. However, existing metal AM technologies operate on a layer-by-layer basis, giving rise to undesirable "staircasing effects" that result in the anisotropic behavior. Additionally, conventional metal printing methods are constrained by printing times, expensive hardware, and limited resolution control. In response to these limitations, this work is dedicated to the development of a cost-effective, ultra-fast layerless metal AM process for crafting intricate 3D metal structures. Low viscous resin was developed to enable continuous printing of metal precursors via mask video projection-based vat photopolymerization, which enable tunable physical properties and superior surface quality. Based on experimental findings, high-density meso- and microscale metallic parts can be printed at speeds orders of magnitude faster than commercial metal AM technologies. Furthermore, printed metallic components display a uniform morphology and microstructure with consistent grain size distribution. A comparative analysis of the surface quality between layer-based and layer-less printed metal structures were conducted. This work has the potential to revolutionize not only the field of AM but also various industries reliant on high-quality metal components, such as aerospace, automotive, and medical devices.