cross section crash boxes

Figure 6.4(b) shows the picture of a fractured welded Al sample in tension. The sample
fractures in the heat affected zone as shown in Figure 6.4(b).
(a) (b)
Figure 6.4. (a) Tensile stress-strain curve of the welded 1050H14 Al and (b) the picture
of a fractured welded Al specimen showing the failure in the heat affected
zone.
6.4. Compression Testing of Commercial Crash Boxes
Figures 6.5 (a) and (b) are the deformation pictures of commercial Al and steel
crash boxes at different displacements, respectively. In Al crash box, two folds form
until 80 mm displacement (Figure 6.5(a)). However, in steel crash box only one fold
forms until about the same displacement. The initial peak load values of both crash
boxes are above 100 kN, and steel crash box shows slightly higher initial peak load
values than Al crash box (110 kN) (Figure 6.6(a)). The mean load values at 50%
deformation are 52 kN and 62 kN for Al and steel crash box, respectively. The SAE
value of Al crash box is however higher than that of steel box, 13.1 kJ kg -1 for Al steel
box and 5.2 kJ kg -1 for steel crash box at 50% deformation (Figure 6.6(b)).
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