Metal 3D Printing
While metal 3D printing
may be relatively new to the additive manufacturing industry, the technology’s evolution since its inception has been remarkable. Metal 3D printing, in a very short time, has added value to a wide range of industries from manufacturing to medical, automotive to aerospace and everything in between. The technology is being used to aid in product development workflows, rapid prototyping, tooling, education and the creation of fully-functional end-use parts.
Despite the evolution of metal 3D printing technologies, or even the emergence of new ones, the tried and true technology of direct metal laser sintering (DMLS
) continues to be a popular solution when it comes to metal additive manufacturing solutions. So, let’s take a more detailed look at direct metal laser sintering, how it works and some of its advantages.
What Is Direct Metal Laser Sintering?
Actually, there is no such thing as thing as Direct Metal Laser Sintering!
EOS coined (trademarked) the term DMLS as ‘Direct Metal Laser Sintering’, undoubtedly in an attempt to brand their technology. Unfortunately, this was a misnomer, and remains very misleading. When using EOS default parameters, a melt pool is formed and a fully-dense structure equivalent to wrought, results.
This is identical to processes referred to as DMLM (Direct Metal Laser Melting) and, thus, we will refer to the process as Direct Metal Laser Solidification for the remainder of this article, as per EOS’ subsequent statements. Read our more in-depth clarification of these two terms.
Direct metal laser solidification (DMLS), aka DMLM, is considered a metal powder bed fusion (MPBF) technology, meaning that parts are printed in a build area (bed) containing finely powdered metal particles that are melted together layer by layer using a laser, to form the finished part. Depending on the specific 3D printer, layer heights on average run between 20 – 60 microns.
One of the main keys to DMLS/DMLM, and how it differs from other similar technologies, is in the melting itself, where high temperatures are used to bring the metal particles to their melting point to fuse them together into a fully-dense piece.
How Does It Work
The first step in any 3D printing project is creating a digital 3D model of the part that is to be printed. Digital 3D models can be created using computer-aided design (CAD) software to model the part from scratch, or if a physical part already exists, a 3D scanner can be used to create a 3D model by generating a digital point cloud or triangular mesh of the part.
The digital model is then loaded into a slicing program that will analyze the model and create the instructions that the 3D printer will use to build the finished part layer by layer. Once the slicing operation is complete, and the file is sent to the 3D printer, the process is fairly automated, other than some general setup.
Once the print run is initiated, a thin layer of powder is then dispersed across the build area. Next, the laser is projected onto the material and then it follows the path for that layer based on the results of the slicing program.
Only the particles in the path of the laser are melted together. This process is repeated layer upon layer, until the part has been completely printed. After a cooling period, the powder that was not melted can be cleared from the build area, and the part can be removed.
Advantages of Direct Metal Laser Solidification/Melting
- Minimized Waste: Additive manufacturing only uses the material required to build the part, so there is minimal waste and decreased material costs.
- Stronger Parts with Reduced Weight: Metal is inherently stronger than plastic and the DMLS/DMLM process can lead to topology optimization and reduced weight.
- Complex Geometries: DMLS/DMLM can create complex geometric parts and assemblies that would not be possible by using traditional manufacturing methods.
- Potential for Fewer Parts: DMLS/DLML leave open opportunity to create fully-formed parts in one pass, whereas conventional methods might require several steps/pieces or sub-assemblies which then must be assembled together to form the final part.
- Wide Range of Metallic Materials to Choose From
- Turnaround Time: Unlike traditional manufacturing methods, there is no tooling to be created or equipment setup, which leads to quicker turnaround times.
The team at GPI Prototype and Manufacturing Services
can help with any and all aspects of your metal 3D printing projects. Contact them today to see how direct metal laser solidification/melting can add value to your operations.