Experimental flattening process on thin-walled sections subjected to quasi-static lateral loading

Bumper crossbeam of a Pride passenger automobile has a rectangular cross-section. This energy absorber structure has the direct effects on human safety during the collisions and accidents. Whatever the mentioned structure absorbs more kinetic energy, the losses reduce during the accidents. Purpose of the present research work is improvement of cross-section geometry of the crossbeam during the lateral compression tests that called flattening process by introducing two new structures, experimentally. Therefore, two structures with W-shape and triangular cross-sections are formed by thin-walled sheets through the bending progress. Each structure is produced with two different plates made from the galvanized iron sheets. In each structure, one of the plates is a flat sheet and another one is a formed sheet by the bending process. The flat plate and the formed one are joined together by the welding to manufacture the crossbeam. Then, they are compressed between two rigid platens, laterally, during the flattening process in the quasi-static condition. Also, to compare energy absorption capability of two manufactured structures with the original rectangular crossbeam of Pride passenger automobile, a structure with rectangular cross-section is produced and laterally compressed during the flattening process. In addition, the effects of initial height, wall thickness and length of the structures are investigated on their energy absorption behaviors. Experimental results show that the sample with W-shape cross-section absorbs the kinetic energy 48% and 297% higher than the structures with rectangular and triangular cross-sections, respectively. So, by considering the same properties, the W-shape structure can use as a bumper crossbeam instead of the original rectangular one in Pride passenger car.