A study on laser bending of tailor machined blanks with various irradiating schemes

Abstract In this work, laser bending of tailor machined blanks has been investigated, both experimentally and numerically. Due to thickness variations in tailor machined blanks, laser bending of these blanks is more complicated than monolithic plates. In these blanks, bending angles and curvatures are different in various sections. Also, multi-curvature bending phenomenon in other words, non-uniform bending in the transverse direction can appear more seriously in tailor machined blanks than monolithic plates. In this paper, a study on laser bending of tailor machined blanks with various irradiating schemes has been performed. For this purpose, three different irradiating schemes i.e. variable speed method (VSM), variable power method (VPM) and variable beam diameter method (VBDM) have been considered. In each method, relevant variable parameter was changed in various sections of tailor machined blank. The results show that using these irradiating methods can reduce differences in bending angles and curvatures of two sections in tailor machined blanks. However, the results show that for the cases investigated in this paper, VSM is a better irradiating scheme than VPM and VBDM. After VSM, the VPM is a suitable choice. It is also concluded that for investigated conditions, VBDM is not a suitable method for laser bending of tailor machined blanks in comparison with VPM and VSM. In other words the results of bending angles and curvature uniformities are not satisfactory with VBDM.

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