Laser-ultrasonic inspection of cold spray additive manufacturing components

Cold spray is a solid state coating technology with high deposition rates that is very suitable for large scale applications of additive manufacturing (AM). For quality control of complex parts, laser ultrasonics is particularly attractive due to its non-contact nature and is well adapted to online implementation. In this study, various inspection results performed off-line on metallic parts produced by the cold spray AM process are presented. Laser ultrasonics combined with the synthetic aperture focusing technique (SAFT) is used to detect flaws and through-thickness distributed porosity is investigated using the laser-ultrasonic backscattered signal. Also, laser shockwave is used to characterize bond strength at the interface between the deposition and the substrate. For post heat treatment of cold spray AM metallic parts, laser ultrasonics is used to monitor in real time recrystallization and sintering. Inspection results from either the top layer or the underside of the substrate are reported and discussed.Cold spray is a solid state coating technology with high deposition rates that is very suitable for large scale applications of additive manufacturing (AM). For quality control of complex parts, laser ultrasonics is particularly attractive due to its non-contact nature and is well adapted to online implementation. In this study, various inspection results performed off-line on metallic parts produced by the cold spray AM process are presented. Laser ultrasonics combined with the synthetic aperture focusing technique (SAFT) is used to detect flaws and through-thickness distributed porosity is investigated using the laser-ultrasonic backscattered signal. Also, laser shockwave is used to characterize bond strength at the interface between the deposition and the substrate. For post heat treatment of cold spray AM metallic parts, laser ultrasonics is used to monitor in real time recrystallization and sintering. Inspection results from either the top layer or the underside of the substrate are reported and disc...