3D printing is an additive manufacturing process that creates physical objects from digital designs. It works by placing thin layers of material, such as liquid or powdered plastic, metal, or cement, and then fusing them together. In the medical industry, 3D printing is used to create organs by first modeling them in 3D with the exact specifications of the recipient's body, then combining living cells and polymer gel (bioink) to print layer by layer. Automakers use 3D printing to test shape and fit, experiment with aesthetic finishes, and ensure that all parts work together as intended.
Precious metals can also be 3D printed in a variety of patterns and designs quickly and cost-effectively. The most common materials used in FDM 3D printing are Nylon 12 for industrial applications, and PLA or ABS for amateur applications. 3D printing is revolutionizing the aerospace industry and has many applications in the medical field. There are two approaches to 3D printing: solid modeling and surface modeling. Solid modeling is faster for simple, non-organic shapes, while surface modeling is faster for more organic shapes.
Stereolithography is an additive 3D printing process that builds layer upon layer by curing a resin with a laser. Directed energy deposition is common in the metal industry and works by connecting a 3D printing apparatus to a multi-axis robotic arm with a nozzle for applying metal powder. Selecting the optimal 3D printing process for a particular part can be difficult, as there are often multiple suitable processes that produce subtle variations in cost and production. In the early 2000s, advances in materials science and the end of many patents made 3D printing affordable for the masses. Today, there are groups that offer students a way to use their school's 3D printers to create prosthetic parts for medical use.