Extrusion

Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is pushed through a die (a certain manufacturing tool) of the desired cross-section. The two main advantages of this process over other manufacturing processes are its ability to create very complex cross-sections, and to work materials that are brittle, because the material only encounters compressive and shear stresses. It also forms parts with an excellent surface finish.