At Mizar, we want to showcase our capabilities and provide information about the various technologies we use. This article covers some questions about the technique of selective laser sintering or SLS. This article covers some questions about the technique of selective laser sintering or SLS.
What is the SLS technique?
SLS or Selective laser sintering technology is an additive manufacturing technology that uses a laser to sinter small, powdered polymer particles into a solid structure based on a 3D model. It is a technique with a great capacity to generate resistant and functional parts, including very complex geometry parts. It is a technique with a great capacity to generate resistant and functional parts, including very complex geometry parts.
With a low cost per part and a high level of productivity, this technology is ideal for a wide variety of applications, from rapid prototyping to small-batch manufacturing, rapid product launch, or custom manufacturing.
Selective laser sintering is a rapid prototyping additive printing technique. The technique consists of depositing a layer of powder (a few tenths of a millimetre thick) in a vat previously heated to a temperature slightly below the melting point of the powder. Next, a high-power laser (e.g., CO2) sinters the powder at selected points, causing the particles to fuse and solidify.
The technology
The production of objects by SLS requires the use of a high-power laser (e.g., a CO2 laser) to fuse small particles of plastic or metal (also ceramic or glass) into the desired three-dimensional shape.
The laser selectively fuses material in powder form in a cuvette by scanning thin transverse layers that are generating the three-dimensional object. As for the dimensional information of the part to be printed, this comes from a computer file that has been generated or previously scanned. When a layer is formed, the powder container is lowered the distance equivalent to the thickness of the layer previously formed and a new layer of material is added to the surface. This process is repeated according to the layers needed to create the object.
In contrast to other additive manufacturing processes, the SLS technique does not require supports. After printing, the parts stay completely encapsulated in the powder, which acts as a support. This powder container must cool down before the part can be cleaned and post-processed. This can take up to 12 hours. The parts are then cleaned with compressed air or other cleaning means and ready for use or further processing.
Applications
SLS is the most suitable technology for the direct production of functionalparts, prototypes and serial parts.
Although it was initially aimed at the manufacture of rapid prototypes, it soon began to be used for the manufacture of serial parts. In addition, its ability to produce parts of very complex geometry from digital CAD models also makes it a growing technology. The parts obtained with this technology are durable and resistant.
Thus, this technique is used in contexts such as aerospace and automotive, consumer products, industrial products, and the architecture and construction industry.
SLS functional parts can be used for drones, in robotics, special machinery, sports equipment, footwear, orthopaedic technology or medical devices.
Materials
The materials used by Mizar Additive for this technology are:
- Polyamide 12 white
- Polyamide 12 natural with flame retardant or glass-reinforced
- Polyamide 11
- Polystyrene
Advantages of the SLS
Selective laser sintering has many advantages for designers and engineers. Let’s look at these advantages:
- This technique allows testingefficient project designs and manufacturing processes.
- It also allows you to use different materials.
- It can facilitate the creation of conceptual models and parts for functional testing, as well as the creation of prototypes of complex designs; it admits all necessary iterations to improve the design of the product by simply modifying the 3D file.
- This technology provides shortdelivery timesas compared to traditional manufacturing techniques.
- It offers the possibility of manufacturing many parts at once, quickly and efficiently.
- It allows different surface finishes to be applied.
- It’s especially recommended for short series of small (even medium) parts.
- It delivers absolute designfreedomas no supports are needed.
- This technique offers the interesting possibility of nesting pieces inside one another.
At Mizar, we have extensive experience in the manufacture by laser sintering of polymers in the EOS P396 system, in addition to our own capabilities. We offer customised end-to-end solutions for our customers; find out more here.
