SAF technology promises production-scale 3D printing

2 min read

Stratasys has revealed details about its H Series, a forthcoming line of powder bed fusion-based 3D printers for volume manufacturing powered by Selective Absorption Fusion (SAF) technology.

SAF technology
Image: Stratasys

Representing the culmination of over a decade of research and development, Stratasys state that SAF-based 3D printers will deliver a competitive cost per part at production level throughput along with part quality, consistency, and reliability ‘that ensures satisfaction and high production yield’.

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In use, SAF technology employs a counter-rotating roller to coat powder layers onto a print bed and prints absorber fluid to image the part layers.  The imaged layers are fused by passing an IR lamp over the entire span of the print bed. According to Stratasys, SAF technology performs these steps in the same direction across the print bed to provide a uniform thermal experience – and part consistency – for all printed parts regardless of their placement in the build.

SAF’s so-called Big Wave powder management system ensures the necessary powder is distributed across the whole print bed, maintaining a large, thermally stable wave of powder. Any overflow is recirculated, minimising thermal exposure and reducing powder ageing, resulting in less fresh powder required and lower operational costs.

SAF selectively jets high energy-absorption HAF fluid onto areas of a layer of powder-form material in one full-width pass. Xaar 1003 GSU6U piezoelectric print heads jet single or multiple drops of the fluid to produce either fine detail or large areas.

According to Professor Neil Hopkinson, director of technology at Xaar 3D and original inventor of the technology behind SAF, the print heads use bulk piezo inkjet printing working in chevron mode.

Image: Stratasys

Specific details about SAF’s powders and fluids have not been released at this time, but Prof Hopkinson said several fluids are ‘compatible with our print heads and ideal for use in industrial manufacturing.’ Similarly, the new platform has ‘made parts from a wide range of material types ranging from engineering polymers to elastomers.’

“SAF has built on the original ideas behind High-Speed Sintering (HSS) but taken it forward in a number of ways to remove sources of variability in the process,” he said. “For example, SAF employs a process architecture that ensures all fused particles on the bed surface experience the same time/temperature profile as each other irrespective of where they are on the part bed surface. Also, our Big Wave powder handling system maintains a thermally stable mound of powder when distributing powder across the bed. These innovations are at the heart of our drive for consistency.”

Commercial availability of 3D printers based on SAF technology is currently expected in the third quarter of 2021.

Stratasys is hosting a live conversation on LinkedIn and Facebook on April 7, during which Stratasys leaders and Prof Hopkinson, will share more information and take questions about the technology.