What is the primary process used in Fused Deposition Modeling (FDM)?

In Fused Deposition Modeling (FDM), the primary process involves the extrusion of a filament, typically made of thermoplastic material such as PLA or ABS. During this process, the filament is heated until it reaches a semi-liquid state and then expelled through a nozzle. This semi-liquid material is then deposited layer by layer to create a three-dimensional object. This technique allows for precise control over the shape and dimensions of the final part as each layer bonds with the previous one upon cooling and solidifying.

The process is distinct from other methods such as those that involve layering and bonding sheets of material, using a moving laser beam to sinter powders, or hardening photopolymers with lasers. Each of these alternatives employs different materials and mechanisms, making them suitable for a variety of applications but not representative of the FDM technique. By focusing on the filament extrusion process, we can appreciate how FDM accurately creates detailed structures and objects through a straightforward method of material deposition.