Which of the following processes is most commonly used for 3D printing in plastic?

Material Extrusion is the most widely used process for 3D printing plastic primarily due to its accessibility, cost-effectiveness, and ease of use. This method involves melting and extruding thermoplastic materials through a heated nozzle to build parts layer by layer. It is commonly associated with popular desktop 3D printers, such as those using Fused Deposition Modeling (FDM), making it a favorite among hobbyists and professionals alike for prototyping and production applications.

The simplicity of Material Extrusion allows for rapid production and versatility in design, as it accommodates a wide range of thermoplastic materials, including ABS, PLA, and PETG. Additionally, the technology is user-friendly, enabling users to create complex geometries with minimal setup.

In contrast, other processes like Selective Laser Sintering and Electron Beam Melting are often used for more specialized applications, primarily involving metals and certain polymers in industrial settings. Binder Jetting, while applicable for plastics, is less common for 3D printing with thermoplastics compared to Material Extrusion. Thus, the popularity and effectiveness of Material Extrusion make it the predominant choice for 3D printing plastic.