Life Predict and Simulation of the Copper Wire in Flexible Printed Circuit Board
Fatigue failure of the circuit board's research focuses on the influence to the circuit board of vibration of rigid circuit board type, distribution of Electronic Components on the board etc. And there is relatively little research to the flexible circuit board's fatigue life research. Local stress-strain method is used to predict the fatigue life. Simulate actual fatigue test load conditions to established finite element model of flexible printed circuit board. Perform fatigue analysis under the periodicity stress. Drawn fatigue life of copper wire in different loading conditions. There is guiding significance to the follow-up test.
Single hole at constrained location for stress analysis in PCB plate bending
In this paper, simulation on the bending process of PCB during depaneling was done. The stress response during the bending process was evaluated using a computational program Ansys version 11. Two PCB plate model were developed: one of the model with single hole and other model without hole. The stress response of the two models were then compared. From the simulation, it has been observed that the value of stress response of the PCB increases with increasing displacement height. The PCB model with single hole exhibited higher stress compared to the PCB model without hole. Highest stress response was obtained at the displacement height of 5cm for both models.
Shock-excited vibrations of a conservative Duffing oscillator with application to shock protection in portable electronics
Abstract Shock-excited vibrations of a conservative Duffing oscillator are examined in application to shock protection of a vulnerable product during accidental drop. We show that a hard characteristic of the oscillator might be advisable for a product which is able to withstand high accelerations (decelerations), while the maximum displacement has to be made small by any means. On the other hand, application of a spring with a soft characteristic can result in appreciably lower maximum accelerations (decelerations) than in a linear system and therefore can be recommended in the case when the requirement for the lowest displacement possible is not very stringent. However, if the drop height is not known with certainty (which is typically the case) the advantages of a soft spring cannot be utilized to the full extent, because of the possibility of a “rigid impact”. In such a case a probabilistic approach can be effectively used to design a soft spring with a low enough probability of a rigid impact. The obtained results can be helpful, particularly, when designing spring protectors in portable electronics. The author believes that these results can be useful for a rather broad class of nonlinear springs, not necessarily with cubic restoring forces.