Collaborative Research: Innovations in Net-Shape Composite Fabrication through Microscale Modeling of Melt Infiltration

许多重要的复合材料是通过熔融渗透法制备的，其中聚合物或金属渗透到纤维预制件中。为了最大限度地减少后处理和机加工，最好直接从浸渍步骤中创建零件，这是一种称为净成形制造的过程。虽然数值模拟是工艺设计的关键部分，但标准模型是在连续尺度上操作的（即，下面的纤维基质被视为连续相）。这种方法是必要的实际原因，但它需要显着的非线性生成空间平均的本构方程和参数。此外，目前的经验技术不能有效地占重要的microcscale现象，如纤维的各向异性，润湿效应，和空隙形成在impregnation.In这个合作研究项目进行的研究人员在路易斯安那州立大学州立大学，国家的最先进的微观建模技术将被应用到浸渍过程中，这将允许使用第一原理进行分析。将进行实验，以帮助模型的开发，并验证其定量能力。在研究的第二阶段，微尺度模拟的结果将按比例放大并转移到净形状制造的连续尺度模型中。最终目标是这种多尺度方法取代与当前方法相关的大部分非线性，从而改进制造技术。 该项目的协作性质将为本科生和研究生提供独特的学习机会，来自路易斯安那州立大学的研究生参加杜兰大学研究的实验方面，来自两个机构的本科生参加路易斯安那州立大学的研究会议。此外，积极参与路易斯安那州少数民族参与联盟计划为代表性不足的群体的学生提供夏季研究机会。

Many important composite materials are made by melt infiltration, in which polymers or metals are infiltrated into fibrous preforms. To minimize post-processing and machining, it is desirable to create parts directly from the impregnation step, a procedure called net-shape fabrication. While numerical simulation is a crucial part of process design, standard models operate at the continuum scale (i.e., the underlying fiber matrix is viewed as a continuum phase). This approach is necessary for practical reasons, but it requires significant empiricism to generate spatially averaged constitutive equations and parameters. Furthermore, current empirical techniques do not effectively account for important microcscale phenomena such as fiber anisotropy, wetting effects, and void formation during impregnation.In this collaborative research project conducted by researchers at Louisiana State University and Tulane University, state-of-the-art microscale modeling techniques will be applied to the impregnation process, which will allow analyses to be performed using first principles. Experiments will be performed to aid in the model development and to validate its quantitative capabilities. In a second phase of the research, results from the microscale simulations will be scaled up and transferred to continuum-scale models for net-shape fabrication. The ultimate goal is for this multiple-scale approach to replace much of the empiricism associated with current methods, thereby improving fabrication techniques. The collaborative nature of this project will provide unique learning opportunities for undergraduate and graduate students, with graduate students from LSU participating in experimental aspects of the research at Tulane, and undergraduates from both institutions being included in research meetings at LSU. In addition, active participation in the Louisiana Alliance for Minority Participation is planed to provide summer research opportunities for students from under-represented groups.