A recent breakthrough in 3D printing has the potential to overcome significant limitations in the technology. Curiously, the technology draws inspiration from a 19th-century source: the pointillist painting technique of French artist Georges Seurat.
3D printing has been celebrated as a manufacturing technology set to disrupt a wide range of industries, including automotive, aerospace, and building construction. Although progress has been made in recent years, 3D printing – or additive manufacturing as it is also known – continues to come up against significant technological limitations. Speed remains the most important obstacle. Small components can take hours to print, which can be tolerable when prototyping ideas or making custom artifacts, but not competitive with mass production. As a result, additive manufacturing has remained a niche process best suited for design iterations and one-off, expensive objects.
Conventional 3D printers involve continuous material deposits, layer by layer. Each layer is actually a thin cross-section of the final intended object. A variety of factors contribute to the time required for printing: more complex geometries, larger scales and more refined surface features require more time. The thickness of each layer also contributes to duration, with thinner layers requiring more time due to an increased number of material passes. Depending on these factors, a small object may require 30 minutes to several days to manufacture, which does not include any post-processing step.
In a new approach, objects can be printed all at once. The connection to pointillism is the way the laser used to sinter the powdered material is distributed into several individual beams. Leading this breakthrough is the Wilmington, Mass.-based company. Seurat Technologies– named after the painter himself – who can create metallic objects with a 2.3 million pixel laser. Each pixel effectively welds metal powders into adjacent layers based on a highly detailed 3D map. According to maker, the technique makes it possible to make “entire renderings at once in a single defined area”. This holistic ability is aptly called “area impression”. In 2D printing, analogies to surface printing are inkjet or laser capabilities, which can generate prints in a single pass. In contrast, typical 3D printers are more like the now obsolete printers pen plotters (remember those?), or the process of manually drawing content, one line at a time.
Seurat Technologies co-founder James DeMuth developed the idea of surface printing in 2009 as a research scientist at Lawrence Livermore National Laboratory, based in California. He considered using 3D printing to make fusion chambers for a nuclear fusion power project using specialty alloys. However, the slowness of the existing technology made it unusable: DeMuth calculated that it would take 200 years build a single chamber! He then looked at how resolution and print speed characteristics could be decoupled to speed up the additive manufacturing process. His eureka idea was to spread the laser in a pattern resembling the virtual model. “What if each pixel could function as an individual laser? ” he asked. “If possible, each pixel in the pattern would have the defining feature as its own independent beam, all with the optical simplicity of a single beam line.”
To make area printing possible, DeMuth took advantage of another LLNL technology, an optically-addressed light valve, which enabled the projection of high-resolution images composed of laser pixels. By modifying the architecture of the system using this method, the surface impression was born. In 2015, he founded Seurat Technologies with his partner Erik Toomre, and today the company complaints it can fabricate metal objects 10 times faster than standard laser powder bed fusion technology – and that speed will increase 100 times in three years. DeMuth also predicts that the price of its surface-printed components will fall by 2030, a claim supported by a peer-reviewed scientific article which Demuth co-wrote for Additive manufacturing, “Physics of large-area pulsed laser powder bed fusion.” .
Once pointillist printing from Seurat Technologies becomes faster and cheaper than conventional metalworking processes, as expected (and yields products of equal or better quality), the disruptive technology will be ready to transform industrial production. as we know it. For example, in building construction, surface printing is likely to shape ornamental metal components in the short term; eventually, it might be possible to print the buildings themselves by projecting a virtual model onto a site.
The opinions and conclusions of this author are not necessarily those of ARCHITECT magazine or the American Institute of Architects.