Effect of laser peen forming process parameters on bending and surface quality of Ti-6Al-4V sheets

Deformation by design: data-driven approach to predict and modify deformation in thin Ti-6Al-4V sheets using laser peen forming

“…10b, which lie within the ± 10 % tolerance level. Yet, larger deviations from the target deformation profile (about −0.18 mm) were observed at both ends of the specimen which might be due to foil delamination during peening (as reported by Sala et al (2022)). As a result,it can be inferred that pre-bent specimens with constant arc radius can be made entirely flat by successfully applying LPF; however, a maximum deviation of ± 0.2 mm can occur due to the limitations of the ANN prediction.…”

“…The current study has certain limitations for the process, namely, the laser energy must not exceed 3.0 J and the number of peening sequences must be limited to four. This is because using more laser energy causes damage to the sacrificial overlay, and increasing the peening sequences over four does not result in significant additional deformation in Ti-6Al-4V sheets, as reported in the work of Sala et al (2022). For practical applications, it could be desired to have operational process parameter constraints such as the laser energy (E L ) and the number of sequences (n), which can further reduce the occurrence of multiple matches of D k (x).…”

“…3). Considered LPF process-related parameters that are primarily varied are laser energy (E L ), number of peening sequences (n), and thickness of the LPF specimen (T ) since they have a higher influence on the deformation in the treated region (Sala et al (2022)) as well as other experimental process parameters (however not varied) such as the area of cross-section of the focused laser beam (A f ) and duration of the laser pulse (τ ). Material parameters, namely Young's modulus (E), density (ρ), and the wave speed (C = √ E/ρ, which is a measure of the speed of transverse propagation of shockwaves through the thickness of the specimen during LPF) are considered to encapsulate the material related effects into the developed ANN model.…”

“…This distribution of plastic strain is responsible for the deformation direction in the treated region as described in the work of Hu et al (2010b). LPF is successfully applied to a wide range of materials such as pure aluminum (Sagisaka et al, 2009;Hu et al, 2010b), aluminum alloy 2024-T351 (Zhou et al, 2018), titanium alloy Ti-6Al-4V (Su et al, 2020;Sala et al, 2022), and glass-reinforced epoxy laminate aluminum composites (Hu et al, 2016). A major advantage of LPF in comparison to traditional forming processes is that the compressive stresses induced at the surface reduce the risk of tensile cracks during the forming process.…”