Creep modeling of precision adhesive joints in opto-electronic devices

光电器件中精密粘合接头的蠕变建模

• 批准号: 463690-2014
• 负责人: Spelt, Jan
• 金额: $ 1.42万
• 依托单位: University of Toronto
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=577089
• 关键词: Creep; modeling; precision; adhesive; joints

Opto-electronic devices consist of optical elements attached to a substrate; the most common method of fixing these components to the substrate is by means of adhesives. Adhesives are susceptible to creep and stress relaxation under the influence of internal and external stresses, which may lead to subtle perturbation of the position of optical components, thereby affecting performance over time. Opto-mechanical design needs to account for this end of life (EOL) behavior of precision adhesive bonds. There is a lack of predictive model for designing against these mechanisms, leading to rule-of-thumb design criteria and material selection processes. Adhesives may be subjected to residual stresses during the curing process, e.g. due to mismatch in coefficient of thermal expansion (CTE) between the optical elements, adhesive, and the substrate. External stresses arise from forces such as gravity and vibration. In optical devices, the external stresses are typically a fraction of the ultimate material strength and normally creep rupture is not a concern. However, the devices are sensitive to very small changes in position, and therefore even low stress can affect device performance. Finite element analysis (FEA) is a powerful tool in opto-mechanical design, and ideal for modeling stress state due to the above loading for complex product geometry. There are several standard creep models incorporated in commercial FEA software such as ANSYS; however, it is not clear they are applicable to the materials of interest, or to low stress creep behavior. The focus of the proposed collaborative research between Professor Spelt and JDSU Ottawa is to measure the creep properties of candidate adhesives and then develop and evaluate adhesive creep models to be used in FEA software for the prediction of creep in opto-electronic adhesive joints.

光电器件由附着在基板上的光学元件组成;将这些元件固定到基板上的最常见方法是通过粘合剂。在内部和外部应力的影响下，粘合剂易受蠕变和应力松弛的影响，这可能导致光学部件位置的细微扰动，从而随着时间的推移影响性能。光学机械设计需要考虑精密粘合剂粘结的这种寿命终止（EOL）行为。缺乏针对这些机制进行设计的预测模型，导致经验法则设计标准和材料选择过程。 粘合剂在固化过程中可能受到残余应力，例如由于光学元件、粘合剂和基板之间的热膨胀系数（CTE）的失配。 外部应力来自重力和振动等力。在光学器件中，外部应力通常是材料极限强度的一小部分，通常蠕变断裂不是问题。然而，器件对位置的微小变化敏感，因此即使是低应力也会影响器件性能。 有限元分析（FEA）是光学机械设计中的一个强大工具，对于复杂产品几何形状的上述负载建模应力状态是理想的。商业有限元分析软件（如ANSYS）中包含了几种标准蠕变模型;然而，尚不清楚它们是否适用于感兴趣的材料或低应力蠕变行为。 Spelt教授和JDSU渥太华之间拟议的合作研究的重点是测量候选粘合剂的蠕变性能，然后开发和评估用于有限元软件的粘合剂蠕变模型，用于预测光电粘合剂接头的蠕变。