ABSTRACT

The authors study shock absorption characteristics and their measurement methods because test standards and specifications for shock absorbing adhesives are not clearly established. Especially, microscale shock absorbing adhesive characteristics are important for mechanical properties of small-sized mobile electronics with slim, bezel-less design. For this purpose, a piezoelectric force sensor is utilized to evaluate impact response of various adhesives under ball drop impact due to high-frequency data acquisition. Next, the evaluated impact responses are compared with dynamic mechanical analysis results to confirm the viscoelastic material behavior of adhesives. In addition, the impact response is proportionally correlated with the damping factor. In order to characterize both shock absorption and adhesive strength simultaneously, a novel test apparatus for shear impact is devised based on the previous test. The correlation between two mechanical properties is determined by analyzing the change of the impact force transmitted through the adhesive. The degradation of the adhesion strength is described by the damage model, which estimates its change before detachment. The proposed experimental mechanics not only enables a concurrent evaluation of adhesion strength and shock absorption but also assesses required adhesive materials for delicate electronic components.

摘要

作者研究了减震特性及其测量方法，因为减震粘合剂的测试标准和规范尚未明确建立。特别是，微型减震粘合剂特性对于具有纤薄、无边框设计的小型移动电子产品的机械性能非常重要。为此，利用压电力传感器来评估由于高频数据采集而导致的球落冲击下各种粘合剂的冲击响应。接下来，将评估的冲击响应与动态力学分析结果进行比较，以确认粘合剂的粘弹性材料行为。此外，冲击响应与阻尼系数成正比。为了同时表征冲击吸收和粘合强度，在上述试验的基础上设计了一种新型的剪切冲击试验装置。通过分析通过粘合剂传递的冲击力的变化来确定两种机械性能之间的相关性。粘附强度的退化由损伤模型描述，该模型估计其在脱离前的变化。所提出的实验力学不仅可以同时评估粘合强度和减震性，还可以评估精密电子元件所需的粘合材料。估计它在脱离前的变化。所提出的实验力学不仅可以同时评估粘合强度和减震性，还可以评估精密电子元件所需的粘合材料。估计它在脱离前的变化。所提出的实验力学不仅可以同时评估粘合强度和减震性，还可以评估精密电子元件所需的粘合材料。