Pulsed mode laser cutting of sheets for tailored blanks

This paper describes how the laser cutting process can be optimised in such a way that the cut sheets can subsequently be used to laser weld tailored blanks. In a number of systematic laboratory experiments, the effect of cutting speed, assist gas pressure, average laser power and pulse energy were analysed. For quality assessment, the squareness, roughness and dross attachment of laser cut blanks were measured. In all tests, the medium strength steel GA 260 with a thickness of 1.8 mm was used. In this work, it has been successfully demonstrated that the squareness of a cut can be used as a quality item for parameter optimisation of laser cut sheets used for tailored blanks. It was concluded that high quality cut edges with a squareness as small as 0.015 mm may be obtained. Such edges are well suited for subsequent laser welding. (C) 2001 Elsevier Science B.V. All rights reserved.