The metal industry continues to evolve, and one of the most popular evolution is 3-D printing to create metal parts. But how does it work?
Printing is an additive manufacturing process as opposed to a subtractive. Materials are added to a whole rather than taken away. The difference is the process behind carving a figurine from wood and building a figurine from macaroni noodles. The product comes from a process of adding materials.
Whenever fabricating a piece, it is necessary to lay out the order of operations, so here is the order of operations for understanding 3-D printing: materials, tools, and then process.
The main material for 3-D printing is this granular, sand/salt-like metal powder. The powder is an atomized version of the chosen metal. It becomes that powder in a process of atomization where gas (or water) hits the molten metal, freezes it to form these particles. Different metal material can undergo this process, such as steel, titanium, and aluminum.
The tools for 3-D printing include an oven and a laser. The oven has a build platform in it, where the atomized metal particles lay. The laser is a high heat beam aimed from the top of the oven onto the platform.
With these materials and tools, the process goes like this:
The oven heats up and fills up with inert gas (argon) to prevent oxidation.
The powder spreads over the build platform in the oven in a thin layer.
The laser concentrates its beam on the powdered platform and fuses the particles together.
The platform moves minimally spreading powder over the fused layer.
The laser concentrates its beam on the powdered platform again, forming the next microscopic layer.
After every layer is fused, the oven bakes the product, preventing any division of metal particles.
The product is cut from the platform and cooled.
The process in essence is about layers. Successive layers are formed and fused to the previous layers, resulting in a product without parts made with particles. That above process is the basics of 3D printing with metal. Other techniques, tools, and material involve the process with more complexity.
Who knows, maybe one day we’ll print 3D railing.