基于疲劳累积损伤等效理论的PCB板振动加速试验研究

目的建立小样本情况下,通过试验及仿真结合求解PCB板在随机振动激励下的振动加速因子的方法。方法以疲劳累计损伤等效为研究基础,以PCB板为研究对象,通过实验室的动力学环境模拟试验,在施加相同谱型不同量级的随机激励载荷下的振动加速因子,并通过采用试验数据对仿真局部模型修正的方法得出PCB板在随机振动激励载荷下的振动加速因子。结果通过试验数据与仿真计算结果的对比,两种方法得出的振动加速因子的误差在5%以内,满足工程实践精度要求。且进一步的证实了该方法的可行性。结论对于不同种类的PCB板在进行小样本摸底试验及随机振动仿真计算的前提下,确定电路板产品的薄弱位置,之后通过疲劳仿真计算局部的疲劳寿命便可以求得一定精度要求下的振动加速因子。

Vibration Acceleration Test of Printed Circuit Board Based on Equivalent Theory of Fatigue Cumulative Damage

Objective To establish a method for vibration acceleration factor of printed circuit board under random vibration excitations by experiment and simulation in combination with small samples. Methods Based on fatigue cumulative damage equivalence, the printed circuit board was taken as the research object, to obtain the vibration acceleration factor of printed circuit board under the random excitation load through the dynamic simulation experiment in the laboratory, with the application of random excitation of the same spectrum type but different magnitude, based on modifying the simulation on local model by the experimental data. Results By comparing the experimental data with the simulation results, the error of the vibration acceleration factor obtained by the two methods was within 5%, which met the requirements of engineering practice accuracy. It also further confirmed the feasibility of this method. Conclusion For different kinds of printed circuit boards under the premise of small sample test and random vibration simulation calculation, it is able to determine the weak position of the circuit board products, then calculate the local fatigue life through the fatigue simulation to get vibration acceleration factor of certain precision.