3D Metal Printing Is the Future

With the introduction of affordable 3D printers, individuals and businesses now have the ability to produce one-off objects and quickly fabricate prototypes like never before. Despite the great technological advances that have been made in the last few years, there are still some issues that need to be overcome, especially with lower-cost models. Acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) are currently the dominant material choices for consumer-oriented devices, but the characteristics of these plastics limit what can be created. Their relatively low melting points preclude high-temperature use, and their mechanical traits leave much to be desired in demanding environments requiring high strength and wear resistance.

Though 3D printers using metal already exist, their stratospheric price limits their use to larger enterprises and puts them out of reach of the average person. Engineering metals are also incompatible with fused deposition modeling, by far the cheapest and most popular method of printing. There are two primary technologies that can use metal: selective laser sintering (SLS) and selective laser melting (SLM). SLS uses a precisely-controlled high-intensity laser to sinter extremely small areas of a powdered feed based on a CAD file, while SLM is similar but fully melts its target instead of sintering it. Both have the capability to be used with a variety of metals, but SLS is better for materials like tungsten with extremely high melting points.

As devices using laser-based processes become simpler to manufacture, their adoption will increase rapidly among all user types. Compared to common machining methods, they offer the ability to precisely create complex and durable objects economically and without human intervention. They also enable the easy processing of metals which are difficult to shape using conventional CNC techniques, such as Inconel and other superalloys that are very prone to work hardening. Additionally, 3D printing has the potential to be less wasteful than lathing and milling, as 3D printing is an additive process as opposed to a subtractive one that removes material from a larger workpiece.

Thermoplastic-based 3D printers will almost certainly continue to explode in popularity for general purposes, but printers using metal will complement them for objects requiring superior mechanical and thermal properties. As the cost of purchasing and maintaining SLS and SLM printers goes down, they may even entirely replace traditional manufacturing techniques in a wide array of applications.