OVERCOMP: Interface Formation and Bond Strength Prediction in Composite Injection Overmoulding

OVERCOMP：复合材料注塑包覆成型中的界面形成和粘合强度预测

• 批准号: EP/X041360/1
• 负责人: M. Ali Aravand
• 金额: $ 34.51万
• 依托单位: Queen's University Belfast
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FX041360%2F1
• 关键词: OVERCOMP; Interface; Formation; Bond; Strength

The rapid growth of the global composite market is primarily driven by the ever-more critical need for lightweighting, especially in the automotive and aerospace sectors constituting over 70% of the UK's demand for composites. The increasing need for high-volume manufacture of composite components cannot be addressed by solely relying on time-consuming traditional composite processing technologies. This is one of the main factors contributing to the UK's reliance on non-domestic production, especially in the automotive industry, where over 50% of the required composite parts are currently imported. High-speed manufacture of near-net-shape hybrid thermoplastic composite components via the highly automated injection over-moulding process (or hybrid injection moulding) is arguably one of the only available solutions to address such a significant demand. Composite injection overmoulding is characterised by its capability to manufacture selectively reinforced, highly complex multi-material components within a few minutes, thereby eliminating several hours-long manufacturing steps that would otherwise be required to produce a part at a similar level of complexity. This will, in turn, largely reduce the waste formation, carbon footprint, and by-to-fly ratio. However, despite these advantages, the adoption of this technology has been hampered by the inconsistent and unpredictable performance of the overmoulded components under loading, predominantly caused by a premature failure at the interface. The lack of a fundamental understanding of the interface formation between the injected polymer and the thermoplastic composite insert is the underlying reason for the current inability to control the bond strength and hence the performance of the overmoulded composite. The complexity of the problem mainly arises from the multitude of factors that affect the interpenetration of the polymer chains and at the interface. Even the slightest changes in processing conditions or the composition of the injected polymer or the thermoplastic insert can significantly affect the bonding quality and hence the service life of the components. The absence of a reliable method to support a high-confidence prediction of the structural performance of overmoulded components has left the manufacturers with no other option but to consider costly trials or resort to other, often highly time-consuming labour-intensive multistep alternative processes. To address this gap in the knowledge base, the OVERCOMP project aims to deliver a reliable multi-scale model to predict the interfacial strength between the two thermoplastic phases involved in an overmoulded component. To this end, the project will focus on the three main aspects that contribute to interface formation during overmoulding. These include (i) heat transfer and rheology, (ii) material compatibility; and (iii) time and temperature-dependent interdiffusion of the polymer chain at the interface (healing). This way, the model will ensure a complete picture of the interface formation during overmoulding and reduce the risk of transitioning to this processing method. This model will enable the manufacturers and part designers to make informed decisions during the material selection step and have a clear picture of the part performance before undertaking to manufacture.

全球复合材料市场的快速增长主要是由日益迫切的轻量化需求推动的，特别是汽车和航空航天领域，占英国复合材料需求的 70% 以上。仅依靠耗时的传统复合材料加工技术无法满足大批量制造复合材料部件日益增长的需求。这是导致英国依赖非国内生产的主要因素之一，特别是在汽车行业，目前该行业所需的复合材料零件超过 50% 是进口的。通过高度自动化的注塑包覆成型工艺（或混合注塑成型）高速制造近净形状混合热塑性复合材料部件可以说是满足如此巨大需求的唯一可用解决方案之一。复合材料注塑包覆成型的特点是能够在几分钟内制造选择性增强的高度复杂的多材料部件，从而消除了生产类似复杂程度的零件所需的长达数小时的制造步骤。反过来，这将大大减少废物形成、碳足迹和飞行比例。然而，尽管有这些优点，但该技术的采用受到了包覆成型部件在负载下性能不一致且不可预测的阻碍，这主要是由于界面处的过早失效造成的。对注射聚合物和热塑性复合材料嵌件之间的界面形成缺乏基本了解是目前无法控制粘合强度以及包覆成型复合材料性能的根本原因。问题的复杂性主要源于影响聚合物链和界面相互渗透的众多因素。即使加工条件或注射聚合物或热塑性嵌件的成分发生最轻微的变化，也会显着影响粘合质量，从而影响部件的使用寿命。由于缺乏可靠的方法来支持对包覆成型部件的结构性能进行高度可信的预测，制造商别无选择，只能考虑昂贵的试验或诉诸其他通常非常耗时、劳动密集型的多步骤替代工艺。 为了弥补知识库中的这一空白，OVERCOMP 项目旨在提供可靠的多尺度模型来预测包覆成型组件中涉及的两个热塑性相之间的界面强度。为此，该项目将重点关注包覆成型过程中有助于界面形成的三个主要方面。其中包括 (i) 传热和流变学，(ii) 材料兼容性； (iii) 界面处聚合物链随时间和温度的相互扩散（愈合）。这样，该模型将确保包覆成型过程中界面形成的完整图像，并降低过渡到这种处理方法的风险。该模型将使制造商和零件设计师能够在材料选择步骤中做出明智的决定，并在开始制造之前清楚地了解零件的性能。