What is SAF Technology and How Does it Work?

By Dennis Barnum on

The demand for reliable and accurate production-level additive manufacturing is growing exponentially, as companies were faced with crippling supply chain issues due to scarcity of raw materials and inhibited labor forces during the Covid-19 crisis. Stratasys has answered this call by expanding their polymeric 3D printing capabilities into SLA and DLP with acquisitions of companies such as Origin and RPS, and most recently, Stratasys continues to grow, by entering into the powder based additive manufacturing market with the introduction of SAF (Selective Absorption Fusion) powder bed fusion technology.

What is SAF Technology?

Selective Absorption Fusion is the 3D printing technology behind the new H Series production platform being introduced by Stratasys as the latest addition to the additive manufacturing portfolio. SAF is one category of powder bed fusion 3D printing processes and uses an infrared-absorbing fluid to help fuse the polymer powder. This fluid is precisely placed, layer by layer, to create the shape of the part. When the infrared-sensitive fluid is exposed to the printer’s fusing lamps, it heats up to a higher temperature than the surrounding material which “selectively” fuses the powdered particles together (hence the name) but leaves the adjacent material unfused.

How is SAF Technology Different?

While SAF technology bears a resemblance to how typical PBF (Powder Bed Fusion) technology is featured on other systems, SAF successfully disaffiliates itself by boasting a uniform, thermal experience for parts, no matter where they may be in the build volume. The thermal uniformity that SAF provides is the key driver behind part consistency and reliability to be competitive at production scale.


Another key differentiator, with SAF as compared to other powder-based technologies, is the use of a single High Absorption Fluid (HAF). This eliminates the need for a secondary detailing agent.
Additionally, this technology will allow users to “nest” parts in the build volume on a geometry independent basis, enabling the operator to leverage the entire build volume in the x, y, and z directions for multiple parts, jobs, or iterative designs all at once.

How is the Stratasys H Series Different?

Aside from the unique process of SAF itself, the H Series production platform was engineered alongside Xaar, the world’s leading independent manufacturer of piezo-based drop-on-demand inkjet technologies.

SAF Technology Part
SAF Technology Part

These Xaar print heads have proven themselves in previous applications in harsh, undesirable manufacturing conditions, and should prove to be durable and long lasting. Thanks to Xaar’s technology and industrial design, these print heads are positioned as robust non-consumables. Features, such as fluid recirculation, allow the head to be cooled constantly and helps prevent ink sediment deposits from settling in the nozzles. This produces accurate and reliable results even in the most unkind conditions.

The H Series also features Big Wave powder management that will inevitably reduce powder aging by minimizing any unnecessary thermal exposure. Big Wave technology quickly recirculates any overflow powder directly back into the feed which significantly minimizes powder thermal exposure, powder aging and the need to refresh with virgin powder, which in turn lowers operational costs. Together, these design considerations could possibly help lower cost per part and ownership costs by reducing material waste and decreasing unnecessary machine downtime.

How Do I Print with SAF Technology?

SAF technology follows the same processing steps as other powder bed fusion printers, which can be simplified into the following stages:
1. CAD files are input to the system for printing.
2. When parts are being printed, they are embedded in a “cake” of unused, loose powder.
3. After printing, the cake is removed from the printer and allowed to cool. After cooldown, the cake is broken apart to extract the printed parts, with unused powder being collected for re-use.
4. Parts can then be used or post-processed as needed, like with other additive manufacturing processes.

Technology is an exciting new frontier that promotes the freedom of design and part complexity that is akin to additive manufacturing, as well as the reliability, repeatability, and volume that is required for a production scale operation. With significant process advancements over traditional PBF Technologies and hardware implementation designed to last, SAF is positioned to provide users with an extremely competitive price per part and unparalleled part consistency, which is non-negotiable when manufacturing at production scale.

Check out more in this whitepaper, where we review why this new technology is an optimal choice for plastic parts and this article highlighting an application for SAF technology.

Stratasys, H Series, H Series Production Platform, FDM and P3 are trademarks or registered trademarks of Stratasys Ltd. and/or its affiliates. SAF, Selective Absorption Fusion, Big Wave, Xaar, and HAF are trademarks of Xaar companies. All other trademarks are the property of their respective owners.