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.

光电设备由附着在基板上的光学元素组成；将这些组件固定到底物的最常见方法是通过粘合剂。在内部和外部应力的影响下，粘合剂容易受到蠕变和压力松弛的影响，这可能会导致光学成分位置的微妙扰动，从而影响时间的性能。光学机械设计需要考虑到精确粘合键的生命终结（EOL）行为。缺乏针对这些机制设计的预测模型，从而导致了肢体规则的设计标准和材料选择过程。 在固化过程中，粘合剂可能会承受残余应力，例如由于光学元件，粘合剂和底物之间的热膨胀系数（CTE）不匹配。 外部应力是由重力和振动等力引起的。在光学设备中，外部应力通常是最终材料强度的一部分，通常蠕变破裂并不是问题。但是，设备对位置的变化很小，因此即使是低压力也会影响设备性能。 有限元分析（FEA）是光学设计中的强大工具，由于上述复杂产品几何形状的负载而导致应力状态进行建模。商业FEA软件中有几种标准的蠕变模型，例如ANSYS；但是，尚不清楚它们适用于感兴趣的材料或低压力蠕变行为。 教授拼写与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特性，然后开发和评估粘合剂蠕变模型，用于在FEA软件中用于预测光学电子胶接头中的蠕变。