What is SAF 3D printing?
SAF technology or Selective Absorption Fusion uses an infrared-sensitive HAF (High Absorbing Fluid) to fuse particles of polymer powder in discrete layers to build parts.
Stratasys SAF technology uses Big Wave powder management, a proprietary technology that includes powder distribution across a bed, where industrial-grade print heads jet the fluid in prescribed areas to create each layer of the part.
This is followed by exposure to infrared energy, which causes the areas with HAF to melt and fuse. The sequence is repeated until the parts are completed.
SAF technology empowers a powder-based additive manufacturing process that employs industrial-grade technology to achieve higher levels of production of end-use parts.
Key benefits of SAF technology
A cost-effective method for printing functional prototypes, manufacturing aids and high-value, low-volume projects.
One-pass print and fuse, few consumable replacements for minimal downtime and high-nesting densities to meet production demands.
End-use production parts
Real-time powder heating, unique thermal management and broad powder range for a wide spectrum of part properties.
Putting additive manufacturing on a new level
Learn more about SAF technology and how it removes the barriers to higher-volume additive manufacturing production. You can discover the Stratasys H series and how it is making mass production easier, quicker and more flexible.
In FFF processes, materials are extruded through a heated nozzle and deposited on a build platform to form an object. In SAF, materials are formed into droplets and absorbed by airflow into the build platform. This allows finer control of the materials used in the process.
Because the polymer is not melted in the hot end nozzle prior to extrusion, the plastic must be melted in a separate melting zone, such as a water bath or extruder. This reduces the need for expensive equipment required to melt the materials at high temperature.
Polymers absorb energy much quicker when heated to very high temperatures than when they are heated at lower temperatures, which improves overall printing speed and throughput. It also allows for faster heating and cooling cycles to minimise distortion.
Since the polymer droplets are absorbed by the airflow, there is no pressure drop associated with this technique so the air can be re-circulated without slowing the process down. This eliminates the need for an additional air compressor and increases the overall efficiency.
Polymers absorb energy much quicker when heated to very high temperatures than when they are heated at lower temperatures, which improves overall printing speed and throughput. It also allows for faster heating and cooling cycles to minimise distortion in printed parts due to residual thermal stress. Powder bed printing processes require lower temperatures than resin based 3D printing processes and because 3D printers print optimally when the heat is consistently high, SAF saves time and money on other processes due to requiring a lower temperature to print and ultimately get printing.
Plastic materials that are printed using powder bed fusion 3D printers typically have much stronger mechanical properties than those that are printed using other additive manufacturing processes such as SLA or SLS. This is largely due to the fact that the part is built from a solid piece of plastic that is made up of thousands of tiny interconnected fibres. While parts that are printed using traditional methods are generally weaker and more brittle than their 3D printed counterparts, this is not an issue for parts that have been printed using a powder bed fusion 3D printer.
The prints are very durable. Owing to the quality materials and printing techniques used, the print should hold up well over time. This includes exposure to water, sunlight, heat and other potential hazards. It also requires little to no maintenance beyond regular cleaning.
Accuracy varies widely between printers but is hugely dependent on the surface finish of the material. A smoother surface requires fewer passes to build the desired shape than a rougher one, which results in more time spent on the surface and more opportunities for defects to appear. SAF printers are designed with a high resolution that helps to minimise this effect and ensure that the quality of the part remains high.
SAF 3D printing provides extremely accurate results. This is due in part to the printing technique itself as well as the superior materials used in the printing process. The printer incorporates multiple processes to ensure a high-quality print every time. The materials are also specially designed to produce highly-accurate prints that adhere to the original design.
For rapid prototypes, the cost will be low as once the design is finalised the final product is produced quickly and at a lower cost than if printing would be done by hand or using other prototyping methods. Costs for printed objects in a production environment are very low; it is far cheaper to print a large item than to produce it using other methods such as injection moulding or CNC machining.
Some post-processing operations may be required depending on the part design and/or the material being used. These could include washing the printed part to remove support material and cleaning the resin from the build platform to eliminate flash that might interfere with subsequent prints. Due to the nature of the process, however, these operations are typically much less invasive than those required in other printing techniques.
High-resolution 3D prints take approximately four hours to print. This can vary based on the size and complexity of the model being printed. Low-res 3D prints take less than three hours to print.
SAF 3D printing technology works using powder-based materials to create solid objects. SAF printers fuse layers of powder together to create 3D models. Compared to other printing techniques, this method can produce more complex and durable prints in less time. The material used in this process is engineered for precision and durability.