Direct Metal Laser Sintering (DMLS) is widely used in industry and is represented by a huge range of professional 3D printing equipment. Its essence is the reproduction of products based on specified 3D models from special metal powder using a laser. In many respects, direct laser metal sintering resembles selective laser sintering (SLS) and selective laser metal melting (SLM) technologies.

However, they are different techniques with their own advantages and disadvantages. Direct laser sintering of metals is designed for additive manufacturing of metal products of almost any complexity. The high accuracy of the equipment for such 3D printing minimizes errors in reproduction. And the peculiarities of the technique provide products with extremely high durability.

How does 3D printing work?

The basic principle is identical to other 3D printing techniques. The basis for reproducing a physical object is its three-dimensional model in the format supported by the 3D printer. Special software prepares this 3D model for printing, specifying all the necessary parameters for reproducing the object. The prepared file is transferred to the 3D printer, where direct laser sintering of metals begins.

The main “actors” at this stage are the metal powder chamber, the material itself, a special roller for leveling it and a laser (one or more). First, the amount of material required to build one layer is fed into the chamber. The supplied powder is leveled with a special device, the excess is removed. After that, the direct construction of the model begins – sintering of the powder in the shape of the first layer with the help of a laser. Then a new layer of material is fed, leveled, and the laser sinter the second layer of the 3D model. The procedure is repeated until the product is fully reproduced.

Perhaps the main factor that affects literally everything in 3D printing of this type, is the power and number of lasers. And here, not everything is not as simple as it may seem. Laser power affects the speed of printing in a positive way. At the same time, a high speed of reproduction negatively affects the quality of 3D printing. It becomes clear that here you should look for a golden mean. But if you do not want to sacrifice the quality of products, and the speed of printing for you is important – it is worth paying attention to 3D printers with several lasers. This approach allows you to compensate for losses in quality and speed up the reproduction of objects.

Advantages:

  • Virtually waste-free production. All powder that was not used in printing can be reused;
  • Ability to create products of any complexity. Direct laser sintering of metals practically does not limit you in the geometric shape of reproduced products;
  • Possibility of 3D printing of several products simultaneously. It all depends on the dimensions of the 3D model and the size of the powder chamber. With such a device you can easily set up small-scale production of metal products;
  • High speed of creation of physical objects. Literally for a couple of hours you will get a fully finished functional object, which is much faster than the process of injection molding.

From the disadvantages it is worth noting the fact that direct laser sintering of metals is still a technology of layer-by-layer reproduction of objects. Despite all the strength of the finished products, they are not monolithic and cannot fully compete with cast parts. However, the technology is rapidly improving and there is a chance that in the future this disadvantage will be eliminated.