Flexible electronic devices based on thin film/substrate structure are often subjected to thermal environments during operation. This study investigates the nonlinear dynamic response of a corrugated thin film/substrate structure under periodic thermal excitation to assess and ensure its reliability. This paper aims to explore the effects of excitation frequency, thermal amplitude, and pre-strain on the dynamic stability of the structure.
A nonlinear dynamic model considering thermal effects is established based on Euler-Bernoulli beam theory. The governing partial differential equations are discretized using the Galerkin method and solved numerically via the fourth-order Runge–Kutta method. Bifurcation analysis is conducted to determine the critical conditions triggering chaotic vibrations.
The dynamic stability of the thin film/substrate structure is primarily governed by the frequency and amplitude of thermal excitation. Elevated excitation frequencies cause the system to transition from periodic to chaotic vibrations, and pre-strain markedly modifies the stability boundaries. In addition, the influence of excitation amplitude on stability depends on the selected excitation frequency.
This study establishes a thermomechanical modeling framework for analyzing the nonlinear dynamic stability of corrugated thin film/substrate structures under periodic thermal loading. The findings provide essential insights for suppressing chaotic vibrations and offer practical guidance for the robust design of flexible electronics serving in dynamic thermal environments.
