Also popularly known as SLS (Selective Laser Sintering) the process involves fabrication of a 3-Dimensional physical model by the selective melting of polymer powder in a layer by layer fusion. This process uses micro-sized PA based powder which is selectively sintered using a highly focussed CO2 laser beam. During the pre-irradiation stage for each layer, the entire powder bed is heated to a temperature below the sintering temperature for the material in order to reduce the thermal distortions to the part and increase the diffusion rate of atoms in order to obtain an acceptable scanning velocity. The irradiation stage enables solid state sintering between the polymer particles and consequently facilitates fusion of the irradiated layer to the previous sintered one.

The Laser Sintering process is often referred to as a Free Form Fabrication due to its ability to fabricate 3-Dimensional structures directly from digital data. In order to facilitate this process digital design is either created using Computer Aided Design (CAD) or by digital scanning methodologies.

This digital datais converted into an STL (Standard Tessellation Language)file format. The STL file is then digitally sliced into layers equivalent to the layer thickness desired during the fabrication of the part. For each sliced layer, the laser selectively fuses powdered material by scanning cross-sections of the object on the surface of a powder bed.

After each cross-section is scanned, the powder bed is lowered by one layer thickness, a new layer of material is applied on top and the process is repeated until the part is completed.

 Advantages

  • Extremely high design complexity is achievable
  • Parts fabricated from real thermoplastic material,PA based
  • High strength and durability of parts
  • Various surface finishes possible with post processing solutions

Applications

  • Fit and functional prototypes for mechanical and thermal tests
  • Parts can be used for rapid tooling, soft tooling and short run production
  • Ideal for functional testing in load bearing application

EQUIPMENT: EOS 396

Machine Specifications:

  • Machine: EOS P 396
  • Manufacturer:
  • EOS GmbH
  • Build specifications:
  • 340 X 340 X 600 mm
  • Laser Specifications:
  • Type: CO2
  • Max Power: 70 Watts

 Materials

PA 2200 –PA12             

Properties

  • Multipurpose material
  • High strength and stiffness
  • Good chemical resistance

PA 3200 (Glass Filled)

Properties 

  • High Stiffness.
  • Wear resistance.
  • Good thermal properties.
  • High dimensional accuracy
  • Excellent surface quality.

 

PA 2210 FR

Properties

  • Flame ret ardency.
  • Halogen free.
  • Good mechanical properties