A preliminary study on the characterization of laser-bending process of AISI 304 steel sheets by acoustic emission technique

Laser bending is an innovative technology that uses a laser beam to bend metal sheets and/or components. It offers advantages such as lack of equipment, high flexibility, adaptability to different materials (including metal foams), and possibility of automation. Actually, the angle can be measured only after the laser-bending process. The acoustic emission (AE) technique offers a great potential for the “on-time” evaluation of the bending angle: this technique is based on the detection of high-frequency acoustic signals emitted during the phenomena evolution deriving from the deformation and/or fracture of a component/structure. This paper presents an initial approach to understand the relationship between bending angle and the characteristics of the AE signals generated during the laser-material interaction. In this work, a diode laser is used to bend an AISI 304 stainless steel sheet: the laser parameters used and the bending angle obtained were correlated with each other. A useful dependence between laser bending and AE parameters was found.