Direct Metal Lesar Sintering

DMLS (Direct Metal Laser Sintering) is an additive manufacturing method that combines the design flexibility of 3D printing with the mechanical properties of metal. Like in the SLS process, the metal part will be created layer by layer by sintering fine powder particles to fuse them together. A major difference between SLS and DMLS is the sintering temperatures. While polyamide needs to be sintered at a temperature of 160°C to 200°C, metal melts at a temperature around between 1510°C and 1600°C meaning that a more high-wattage laser is needed to reach that temperature.

First a roller will apply a layer of metal powder, then the laser will sinter the powder as per the CAD design, upon completion of the first layer the build platform will move down and the roller will apply a new layer of powder. The process is repeated until the desired part is created. Once completed, the metal part needs to cool down before being extracted. Support structures are automatically generated and built simultaneously in the same material, and are later manually removed.

DMLS 3D printing is ideal for:

  • forward Fully functional parts and tools
  • forward Tooling inserts and cooling channels
  • forward Ductwork, Fixtures or mountings
  • forward Heat exchangers and heatsinks
  • forward Spare parts

Technical Specifications for DMLS

forward Standard Lead time: Minimum 10 working days depending on part size, number of components and finishing requirements lead time may increase.

forward Standard Accuracy: ± 0.3%

forward Layer thickness (resolution): 0.04 mm

forward Minimum Wall thickness: 1mm

forward Max dimensions: 250mm x 250mm x 300 mm. Large parts can be created by assembling individual parts by interlocking designs or gluing them together.

forward Surface finishing and Post Processing: Unfinished parts typically have a rough surface. DMLS parts can be hand-polished or machined surfaces upon request.

Materials

forward Stainless Steel (17-4 PH) is a precipitation hardened stainless steel that is known for its hardness and corrosion resistance. If needing a stainless steel option, select 17-4 PH for its significantly higher tensile strength and yield strength, but recognise that it has far less elongation at break than 316L.

forward Stainless steel 316L is a material used for manufacturing acid and corrosion resistant parts. Select 316L when stainless steel flexibility is needed; 316L is a more malleable material compared to 17-4 PH. Final parts built in 316L receive stress relief application.

forward Aluminum (AlSi10Mg) has good strength -to-weight ratio, high temperature and corrosion resistance, and good fatigue, creep and rupture strength. AlSi10Mg also exhibits thermal and electrical conductivity properties. Final parts built in AlSi10Mg receive stress relief application.

forward Inconel is a high strength, corrosion resistant nickel chromium superalloy ideal for parts that will experience extreme temperatures and mechanical loading. Final parts built in Inconel 718 receive stress relief application.

forward Cobalt Chrome is a superalloy is known for its high strength-to-weight ratio

forward Copper (CuNi2SiCr) is an alloyed copper material, which combines good mechanical properties with thermal and electrical conductivity. This alloy can be used in rough environments where pure copper is not feasible. Copper is structurally stronger, harder, and has higher elongation when compared to AlSi10Mg, which also exhibits thermal and electrical conductivity properties.

forward Titanium (Ti6Al4V) is a workhorse alloy. Versus Ti grade 23 annealed, the mechanical properties of Ti6Al4V are comparable to wrought titanium for tensile strength, elongation, and hardness.

forward Maraging Steel is a pre-alloyed ultra high strength steel in fine powder form. Its composition corresponds to US classification 18% Ni Maraging 300, European 1.2709 and German X3NiCoMoTi 18-9-5. This kind of steel is characterized by having very good mechanical properties, and being easily heat-treatable using a simple thermal age-hardening process to obtain.