Engineering Studies

Forming processes – extrusion

View the PowerPoint presentation in order to answer the following questions related to the extrusion process.

Outline the process of extrusion.
Extrusion is the process of squeezing metal in a closed cavity through a tool, known as a die using either a mechanical or hydraulic press.
Describe a common process to which extrusion could be compared.
The extrusion process is often likened to the squeezing of toothpaste from a tube.
Outline the function of the die in the extrusion process.
The die has a cavity the size and shape of the intended cross-section of the final extruded product.
Identify the types of products that are produced by the extrusion process.
The extrusion process generally produces long, straight metal parts. The cross-sections that can be produced vary from solid round, rectangular, to L-shapes, T-shapes.
Identify and analyse an advantage of the extrusion process.
Extrusion often minimises the need for secondary machining and thereby reduces the cost of production of shaped components.

Identify the types of metals that are commonly used in the cold extrusion process.
Examples of the metals that can be extruded are lead, tin, aluminium alloys, copper, titanium, molydbenum, vanadium, steel.
Outline the advantages of cold extrusion, i.e. extruding metal below its recystallisation temperature.
Advantages of the cold extrusion process are that the manufactured product has good mechanical properties due to severe cold working and good surface finishes as no oxidation takes place.
Identify items that are typically produced by the hot extrusion process.
Typical parts produced by hot extrusions are trim parts used in automatice and construction applications, window frame members, railing and aircraft structural parts.