3D Printing Program Targets Rapid, High-Volume Production of Large Parts

Materials developer Covestro and industrial 3D printer manufacturer voxeljet are collaborating on a material-machine combination for the economical and high-throughput production of large parts by additive manufacturing (AM).  

The voxeljet process in use is high-speed sintering (HSS), and the model specified for the program is the large-format VX1000 HSS printer, which is designed to rapidly print a full part layer in one simultaneous pass across the entire print bed.  

The printer is versatile: it can be automated, will run continuously with minimum supervision, and according to voxeljet allows the cost-efficient production of components that usually cannot be competitively produced by conventional injection molding. The VX1000 HSS has a printing resolution of 360 dpi, job box dimensions of 1,000 by 540 by 400 mm (roughly 39 by 21 by 16 inches) and build volume of 216 L.  

It was developed for polyamide-12 materials but can be set up for most polymers, the company says. 

The HSS process combines the advantages of two widely used AM technologies: selective laser sintering (SLS), a powder technique, and binder jetting.  

The benefits of SLS include fast, robust printing and high dimensional accuracy.  

Binder jet printing uses a similar powder-spreading technique as SLS but adheres parts with a liquid binding agent instead of a laser. As a result, it is a comparatively low-energy process and cost-effective on a per-part basis, prints rapidly and is scalable.  

The companies have jointly developed and qualified a thermoplastic polyurethane (TPU) powder for HSS and are working on a seamless material-process solution for volume manufacturing. 

“Typically, material and processing technology work separately in the value chain, with customers having to figure out how to make them work,” says Geoff Gardner, innovation director for additive manufacturing at Covestro. “Together with voxeljet, we want to remove what is still a barrier to adopting AM on the production floor. Due to its size and speed and constant layer time, HSS offers manufacturers an economic solution for series production.”  

James Reeves, global director of polymer sintering (HSS) at voxeljet adds: “The potential of HSS to process specialty powder materials is tremendous. By offering customers material choices, we accelerate their access to … products.” 

Besides TPUs, materials the companies are considering for the program include thermoplastic elastomers, polybutylene terephthalate and polypropylene.  

Covestro, based in Leverkusen, Germany, was formerly Bayer MaterialScience. Its product specialties include TPUs and polycarbonate, isocyanates, polyols, specialty films and elastomers, and adhesives. U.S. headquarters is in Pittsburgh.  

voxeljet is an international company based in Augsburg, Germany. The U.S. office is in Canton, Mich.