Sun Lei, Yi Wenjun
National Key Laboratory of Transient Physics, Nanjing University of Science & Technology, Nanjing 210018, China.
Sensors (Basel). 2021 Mar 26;21(7):2316. doi: 10.3390/s21072316.
In this article, the influence of shrinkage tensile stress in potting materials on the anti-overload performance of a circuit board was studied. Firstly, the phenomenon of shrinkage tensile stress in common potting materials was analyzed, and it was found that the commonly used potting adhesives displayed large shrinkage characteristics. Secondly, a small experiment was set up to verify that the shrinkage tensile stress of potting adhesives would lead to printed circuit board (PCB) deformation, and the shrinkage stress was contrary to the acceleration direction of overload. Thirdly, the influence of potting adhesives on the overload resistance of the PCB was analyzed. However, the shrinkage tensile stress in the potting adhesive weakened the anti-overload ability of the circuit board. When there was a small amount of expansion stress in the potting adhesive, the overload resistance of the circuit board could be partially increased. From the analysis, it is indicated that a material with a certain expansion property, elasticity, and dense structure should be selected as the potting adhesive. This article provides a reference for improving the overload resistance of electronic devices.
本文研究了灌封材料中的收缩拉应力对电路板抗过载性能的影响。首先，分析了常见灌封材料中的收缩拉应力现象，发现常用的灌封胶表现出较大的收缩特性。其次，进行了一个小实验来验证灌封胶的收缩拉应力会导致印刷电路板（PCB）变形，且收缩应力与过载加速方向相反。第三，分析了灌封胶对PCB抗过载能力的影响。然而，灌封胶中的收缩拉应力削弱了电路板的抗过载能力。当灌封胶中有少量膨胀应力时，电路板的抗过载能力可部分提高。分析表明，应选择具有一定膨胀性能、弹性和致密结构的材料作为灌封胶。本文为提高电子设备的抗过载能力提供了参考。
