Evaluating and modeling the behaviour of 2-D braided composites for cardiovascular catheter development

二维和三维编织复合材料作为结构增强材料已经使用了几十年。近年来，二维编织复合材料已被研究用于非常规应用的新用途，例如导管，其特征直径范围从0.8毫米到4毫米，以及运动器材，其具有不同的形状和紧曲率区域超过其长度。我的研究计划的长期目标是研究，更好地理解和预测基于开放和封闭网格纤维的二维编织复合材料层状结构的行为，这些结构由刚性或柔性树脂基质生产。短期目标是四个项目，它们都面临着来自长期和中期目标的挑战：(1)通过改进编织-芯棒覆盖优化的运动学模型，发展编织复杂形状芯棒的能力。(2)开发一种工具来进行全结构应变测量。(3)分析实验结果，建立准静态载荷下刚性和柔性聚合物基质管状编织体在小到大变形下的弹性行为模型。由于复杂的非线性行为和变形依赖的弹性特性，使用柔性基质对导管至关重要，具有挑战性。(4)研究链径和截面对预测模型的影响。该研究计划预计将对编织复合材料的基础理论和行为理解产生重大影响。它将产生一个庞大的不同形状和大小的编织复合材料实验数据数据库，以充分评估它们的行为和用途。研究结果将适用于通过其他方法和其他单元配置制造的复合材料。这项工作将继续对医疗导管技术产生影响，该技术已经确定了2D开放式网状编织可以解决的设计缺陷。改进的导管技术对患者生活质量的影响，节省时间，改善医生的程序是显而易见的。六名博士，两名硕士和五名本科生将在这个研究项目中接受培训，这些学生是加拿大劳动力非常需要的。

Two- and three- dimensional braided composites have been used for decades as structural reinforcements. In recent years, 2-D braided composites have been studied for novel use in unconventional applications, such as catheters, which have characteristic diameters ranging from 0.8 mm to 4 mm, and sports equipment, which has varying shapes and regions of tight curvature over their lengths. Long term objectives of my research program are to study, understand better and predict the behaviour of open- and closed-mesh fibre-based two-dimensional braided composite laminate-based structures produced with either rigid or flexible resin matrices. Short term objectives are four projects which all meet challenges deriving from long and medium term objectives: (1) Develop the capability to braid over complex-shaped mandrels by improving kinematic models for braid-mandrel coverage optimization. (2) Develop a tool to perform full structure strain measurements. (3) Analyse experimental results and develop models for the elastic behaviour of rigid- and flexible-polymer matrix tubular braids under small to large deformation, in quasi-static loading. The use of flexible matrices, critical to catheters, is challenging because of complex non-linear behaviours and deformation- dependent elastic properties. (4) Investigate strand path and cross section effects on predictive models. The research program is anticipated to have a significant impact on fundamental braided composite materials theory and behavioural understanding. It will produce a large database of experimental data of braided composite with varying shapes and size to assess fully their behaviour and usefulness.The findings will be applicable to composite materials manufactured by other means and other unit cell configurations. This work will continue to have an impact on medical catheter technology, which has identified design weaknesses that can be met by 2D open mesh braiding. The effect of improved catheter technology on patient quality of life, for saving time, and improving the procedure for medical doctors is palpable. Six PhDs, two MSc and five undergraduate students, highly desirable to the Canadian work force, will be trained in this research program.