Aluminium sheet forming

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Discover how aluminium sheet forming processes are classified when following the system for process classification. From compressive to tensile and stretching to cold heading, learn more about sheet forming with aluminium.

The most rational way to classify sheet metal (including sheet aluminum) forming processes is to follow the system for process classification, which is basically a stress state system [1]:

processes with predominantly compressive stresses
processes with combined compressive and tensile stresses
processes with predominantly tensile stresses
processes with bending.

Below is an abbreviated classification of sheet metal forming technologies from the detailed article “Design of Forming Processes: Sheet Metal Forming” by T. Wanheim, which is located in the capital work “Encyclopedia of Aluminum and Its Alloys” – Eds. G.E. Totten, M. Tiryakioğlu, and O. Kessler – 2019. See the original source for more details.

Sheet forming with compressive stresses

To this group belong processes where the flow in the deformation zone mainly is established by a compressive load:

Stretching
Dome forming
Cold heading of cups
Flanging
Coining
Necking-in
Edge rolling
Bulging.

Figure 1 – (a) Plane stretching; (b) three-dimensional stretching

Figure 2 – Dome forming

Figure 3 – Cold heading of cups

Figure 4 – Flanging

Figure 5 – Coining

Figure 6 – Necking in

Figure 7 – Edge rolling

Figure 8 – Bulging

Sheet forming with compressive and tensile stresses

To this group belong processes where the flow in the deformation zone is established by a combination of tensile and compressive stresses. A large part of the sheet metal forming processes belong to this group:

Deep drawing
Rubber forming
Hydro mechanical deep drawing
Spinning
Ironing

Figure 9 – Deep drawing without blank holder

Figure 10 – Principal layout of a conventional deep drawing

Figure 11 – Rubber forming, Guerin process

Figure 12 – Rubber forming, Marform process

Figure 13 – Hydromechanical deep drawing

Figure 14 – Rubber forming, hydroform process

Figure 15 – Conventional spinning

Figure 16 – Shear spinning

Figure 17 – Tube spinning

Figure 18 – Ironing

Sheet forming with tensile stresses

To this group belong processes where the flow in the deformation zone is mainly caused by tensile stresses. This group contains many sheet forming processes:

Stretcher Leveling.
Stretch forming.
Bulging
Expanding
Beading.

Figure 19 – Stretcher leveling

Figure 20 – (a) Stretch forming; (b) stretch-wrap forming

Figure 21 – Bulging

Figure 22 – Expanding

Figure 23 – Beading

Sheet forming with bending

To this group belong processes where the flow in the deformation zone is caused by a bending moment, created either by external compressive or tensile loads or by external moments: