Introduction to Powder Sintering

Powder sintering is the translation of the English name Selective Laser Sintering, whose acronym is SLS. With this technology by  powder sintering or Laser sintering, plastic powder particles are agglomerated thanks to heat and the presence of a laser.  In fact, the chamber where the parts are manufactured is heated up, and a laser is used to sinter the polyamide powder in a thin layer. The part is manufactured in successive layers of 0.10 mm when the process is repeated.

The SLS process produces functional plastic parts with isotropic mechanical properties that can be used for detailed prototyping or low volume production of functional parts.

The printing dimensions of our largest machine allow us to print parts up to 350 x 300 x 420mm

machine park for 3D printing Machine axis 3d printing SLS powder sintering

The benefits of this 3D printing technology

  • Powder sintering technology does not require support structures. The printed parts are held together by the powder that surrounds them.
  • The lasers have a high scanning speed and are extremely accurate (which is different from material deposition printing such as FDM). They allow to print parts with a high precision and a good productivity.
  • SLS 3D printing works with a wide range of materials: metal, polymer, glass, ceramic or composite material.

These advantages make it an ideal technology for:

  • functional models
  • Aerodynamic validation
  • Dimensional, mechanical, thermal validation…
  • Production of mini series up to a few hundred pieces
Powder sintering clip made by Axis
pièces 3d par frittage laser
Maquette 3d par frittage de poudre Axis
Prototypage par frittage de poudre, laser coquillage

Materials and finishes of the SLS

At Axis, we use the following materials:

  • PA 650 (PA 12 – Polyamide)
  • PA 615 glass filled (PA 12 GF)
  • PP (Polypropylene)
  • TPU 70 shores A

And in terms of finishes we offer you

  • Manual cleaning of all surfaces
  • Epoxy impregnation and polishing
  • Moisture recovery
  • priming
  • Painting finishing
  • Metallisation
  • We carry out and validate the assembly of your sub-assemblies

You want to know more about stereolithography? You can consult our material sheets.

Deadlines and part design tips

For the Powder Sintering process, it takes 2 to 6 business days depending on the size and finish of your project. For your mini series (up to a few hundred pieces, please contact us to obtain the deadline).

Regarding the design of your parts, plan for a minimum wall thickness of 0.8mm.

The Powder Sintering in pictures

How does it work?

To be able to obtain a part via the powder sintering technology, several steps are necessary:
  • Preparation :
    • First of all it is essential to have a 3D file thanks to 3D design software in .STEP or .STL format
    • This file is then processed and cut by us into thin 0.10 mm slices.
  • Construction :
    • This information is transmitted to the production machine. This sintering machine is composed of a pilot computer, 2 powder tanks, a platform, a lens and a laser. The construction of the part begins with the platform in the high position, flush with the construction surface of the machine.
    • A thickness of powder is deposited on the platform using a roller or an arm depending on the machine used.
    • Once the machine is closed, it heats up to reach a certain temperature in the construction cabin.
    • Once this temperature is reached, the laser starts up, passes through the lens and heads according to the trajectory calculated by the pilot computer to trace the contours of the part.
    • On contact with the laser, the powder becomes compact and welded because the heat is increased at this precise location to reach the melting point and sinter the material.
    • The platform drops 0.10 mm, then a new layer of powder is deposited on top.
    • The different stages then follow one another: the laser taps on the powder to harden it, the platform descends, the roller or the arm deposits a uniform layer of powder, etc.
    • Once all the successive layers have been produced, the temperature in the passenger compartment drops, the entire production can be accessed.
  • Finishing :
    • The ” cake ” of manufacture then resembles a cube of powder.
    • It is then placed on a sieve and cooled so that its core is not too hot in order to avoid any risk of deformation of the parts.
    • Like archaeological excavations, using brushes and tools we come to find the prototypes produced in the middle of the powder.
    • The parts are then dewaxed, sandblasted, … to remove any excess powder still present.

Our means of production

  • 1 EOS P380: 325 x 325 x 620
  • 2 HQ Sinterstation : 350 x 300 x 420

To learn more about our other means of production in additive manufacturing, do not hesitate to consult our page dedicated to our machines.

Need a quick quote or information on rapid prototyping?

Contact us by form or call us at +33 (0)5 55 06 17 17