What material is most commonly used in fused deposition modeling (FDM)?

Fused deposition modeling (FDM) primarily relies on thermoplastic polymers due to their properties that are well-suited for the additive manufacturing process. These materials are engineered to be extruded through a heated nozzle, allowing them to be deposited in layers to create a three-dimensional object.

Thermoplastic polymers possess several advantages such as ease of processing, excellent adhesion between layers, and a range of mechanical properties that can be tailored for specific applications. Popular thermoplastics used in FDM include polylactic acid (PLA), acrylonitrile butadiene styrene (ABS), and nylon, each offering different strengths, flexibility, and thermal resistance.

In contrast, the other materials listed are not typically used in FDM. Aluminium and composite metal alloys are more relevant to processes like selective laser melting or electron beam melting, which are suited for metal additive manufacturing. Polyethylene, while a type of thermoplastic, is less commonly applied in FDM compared to the other polymers specifically optimized for this technology. Therefore, thermoplastic polymers are the most suitable and prevalent choice in FDM applications.