What is the primary difference between fused deposition modeling and selective laser sintering?

The primary difference lies in the process by which components are built in the two techniques. Fused deposition modeling (FDM) constructs parts by melting and extruding thermoplastic materials through a nozzle, depositing the material layer by layer to create a three-dimensional object. This method relies on thermoplastics such as ABS or PLA, which solidify as they cool, providing the required structural integrity.

In contrast, selective laser sintering (SLS) uses a high-powered laser to selectively fuse powdered materials, typically nylon or other thermoplastics, into a solid structure. The SLS process does not require thermoplastics to be melted and formed in the same manner as FDM. The use of powders allows for different material properties and can lead to complex geometries that may not require support structures due to the surrounding powder providing support during the build process.

This distinction in how materials are utilized and layered is crucial for understanding the operational methodologies of each technology and their applications in manufacturing.