摘要
This study presents an ANSYS-based finite element methodology to predict reflow-induced PCB warpage in an automotive Network Access Device (NAD) module by incorporating viscoelastic prepreg behavior and assembly sequencing using the element birth-and-death technique. Simulations uses a reflow profile with a 250°C peak and assesses the effect of shielding-frame reference temperature across 140-220°C and three solder-attachment configurations. Best agreement with measured warpage is achieved when the shielding-frame reference temperature is set between 140°C and 180°C, and the validated model reproduces measured warpage magnitudes (measured warpage range 80-179 μm; simulated value 133.4 μm) with consistent contour shapes, demonstrating the physical relevance of the chosen reference-temperature window for the frame. Differences in final warpage among the three solder-structure representations are under 10%, indicating that simplified solder modeling can be adopted to reduce modeling effort without appreciable loss of predictive accuracy. The combined use of viscoelastic material characterization and element birth-and-death assembly sequencing enables early-stage identification of warpage risk and supports design/process adjustments to improve yield and reliability in automotive electronic assemblies. © 2026 IEEE.