Three-Point Bending Test and Finite Element Analysis of Flexible Termination Multilayer Ceramic Capacitors

Flexible Termination Multilayer Ceramic Capacitors (FTMLCCs) introduce a flexible electrode layer composed of resin and conductive filler on top of the typical three-layer electrode structure. This flexible layer can absorb significant bending deformation, thus protecting the internal ceramic structure without increasing the capacitor size or compromising its capacitance. In this study, FTMLCC of 1812 product was chosen as the research subject to quantitatively analyze the protective effect of the flexible electrode and the failure mechanism of cracking under bending loads. Simulation analysis was conducted to study the stress and strain distribution of the capacitor after three-point bending. Additionally, bending tests were performed on Multi-layer ceramic capacitors(MLCC) containing flexible electrodes, and a impedance analyzer was employed to address the issue of online monitoring of FTMLCC failures. By combining stress-strain testing to confirm the strain magnitude of the Printed Circuit Board(PCB) during bending, the strain result of PCB in experiments were compared with numerical simulation results to validate the rationality of the numerical model. The failure point of capacitor is located by infrared thermal imaging technology. The electrode structure, the defects of the flexible layer and the failure mode of FTMLCC were studied by metallographic analysis.