Simulation of Inhomogeneous Refractive Index Fields Induced by Hot Tailored Forming Components

For effective quality control in hot forming applications, it is imperative that optical geometry reconstruction is conducted while the workpiece remains in its hot state to ensure the early detection of material distortion effects. This requirement is especially vital in the fabrication of hybrid bulk metal components with locally adapted properties, which are essential to address current challenges and demands on components, as well as to conserve resources. The utilization of hybrid materials results in differing thermal expansion coefficients, which significantly impact the shrinkage behavior of the component. Furthermore, the formation of these components involves exposure to high‐temperature gradients up to 1100 °C, causing the surrounding air to heat up and result in density variations. These variations generate an inhomogeneous refractive index field (IRIF), which substantially affects the surface reconstruction capabilities of optical measurement systems. Understanding the formation and dynamics of these refractive index fields is crucial to minimize uncertainties in optical measurements. This study aims to provide a comprehensive simulation model for the IRIF generated by hot‐forged tailored forming components. Utilizing this model, a priori information on the propagation characteristics of the IRIF can be obtained, thereby facilitating optimized positioning of the measurement system and minimizing reconstruction errors.