SLS

SLS – Selective Laser Sintering

SLS is an advanced industrial 3D printing technology that uses a laser to sinter a fine powder material. This material is most often plastics and various plastic composites, for example with additives of carbon, and glass but also metals like aluminum. During printing, the laser selectively fuses the powder particles layer by layer according to a digital 3D model, resulting in an accurate and detailed print. SLS technology is popular in manufacturing industries for its ability to create complex and durable parts without the need for support structures.

SLS printing process

The whole process takes place in a closed chamber, which is first heated to a temperature just below the melting point of the sintered material. A thin layer of powder is then deposited on the moving bed, onto which the laser-printed layer is drawn. The bed is moved lower and another layer of fresh powder is deposited onto it, into which another layer is drawn and fused with the layer below. The process is repeated until the desired object is made. Sintering is a process in which heat or pressure is applied to form a solid mass of material without melting or liquefying the material. After printing is complete, the entire chamber must cool slowly to prevent shrinkage and deformation. Cleaning of the print is by air and a fine abrasive. After cleaning, the unsintered material is mixed with new powder in a certain proportion and can be reused. The dust particles are 30-60 μm in size.

Advantages of SLS technology:

• High precision and detail – Allows you to create complex geometries with fine detail.
• Durability of parts – The products are strong and durable, suitable for both functional prototypes and final products.
• No need for support structures – Facilitates the printing of complex shapes without additional materials.

Most common use:

• Functional prototypes – Rapid testing of designs and mechanical properties.
• Small and medium batch production – For specialised parts and products with a need for high durability.
• Automotive and aerospace – For the manufacture of lightweight but durable components.

Materials for SLS

PA11, PA12, PA12-GF, PA12-AF, PP

SLS Fun Fact

A single particle of powder commonly used in SLS 3d printing is between 20-80 μm. The human eye can see around 100 μm under the right conditions.