3D printing of metal is done through a range of methods, such as powder bed fusion 3D printing. SLM and DMLS (Selective Laser Melting and Direct Metal Laser Sintering) are two of the most well-known and commonly used among them.
They are similar in a few aspects, like laser scanning and melting/fusing the powder in layers. Both methods also require the same texture of metals as materials. There are a few differences as well, including the basics related to the particle bonding process. SLM melts the powder completely and makes many parts from a single metal powder, whereas DMLS makes parts from a powder that contains different metals and their alloys.
We are going to go over the fundamentals of both these techniques in this post.
How Do SLM and DMLS Work in an Industrial Metal 3D Printer?The two processes used by an industrial metal 3d printer are quite similar. Given below are the steps they involve:
● The printer mechanism releases an inert gas in the build chamber to minimise the metal powder’s oxidation levels.
● It increases the build chamber’s temperature to reach optimal heat levels.
● A high-power laser scans the cross-section of the part after spreading a thin layer of metal powder across the build platform.
● The laser fuses the metal powder particles of metal filament for 3D printers together to create layers. These result in a fully solid component.
● After finishing the scan, the build platform shifts one layer down and spreads a thin layer of powder through the re-coater. It repeats this procedure as many times as it takes to complete the part.
Each part has a support structure that fixes it to the build platform. Since these comprise the same material as the component, it helps manage the deformation and warping that may occur during the process.
The user removes the excess powder after the bin returns to room temperature. Each component also receives heat treatment before detaching it from the build platform. This takes care of any residual stresses that may still be acting on the parts. After this, each part is separated from the build plate through one or more methods, such as wire EDM, cutting or machining.
Uses of SLM and DMLS in an Industrial Metal 3D PrinterBoth these techniques build parts using a wide range of materials including metal alloys, such as aluminium, titanium, stainless steel, etc. These can even process precious metals like silver, gold, and platinum.
Since an industrial metal 3D printer is compatible with superalloys and other high strength metals, it can cover a majority of industrial applications. It has made it simpler to print and process parts that are difficult, expensive, or time-consuming to make using conventional methods.
Pros and Cons of Using an Industrial Metal 3D PrinterHere are the main benefits and shortcomings of using an industrial metal 3D printer:
Advantages● A large build volume 3D printer that uses SLM or DMLS can make complex, bespoke components that traditional manufacturing techniques cannot make successfully.
● Parts made using such methods can be improved easily in terms of performance, weight, and feasibility.
● The resulting components contain superior physical properties thanks to the printer’s compatibility with various materials, such as superalloys.
Disadvantages● Depending on the metal, quantity and other factors, metal 3D printing can be an expensive process. This makes them unsuitable for parts that conventional techniques can manufacture quickly and easily.
● Older designs may have to undergo complex modifications to make them suitable for an industrial metal 3D printer.
● There can be limitations on the build size due to the need for specific manufacturing conditions.
● Already existing designs may not be suitable for metal 3D printing and may need to be altered.