Title: A Validation Study of a Physics-based Tack Model for an Automated Fiber Placement Process Simulation
Authors: Victoria Hutten, Alireza Forghani, Paulo Silva, Curtis Hickmott, Thammaia Sreekantamurthy, Christopher Wohl, Brian Grimsley, Brian Coxon, and Anoush Poursartip
Abstract: Automated Fiber Placement (AFP) offers a fast and more repeatable alternative for the fabrication of complex composite parts compared to traditional methods such as hand lay-up. Despite the performance advantages in the AFP process, geometry and process conditions may introduce defects that are not common in a hand lay-up process (e.g. wrinkles, puckers, fiber bridging, etc.). All of these critical defects are a form of fiber misalignment due to separation of the prepreg slit tape from the substrate. This research project, performed under NASA’s Advanced Composites Project, offers a physics-based framework for simulation of AFP processes with the aim of predicting defects as a function of tool geometry, tow course path, and process conditions including temperature, head speed, pressure, and tow tension. The physics-based framework includes a representation of the AFP head, the slit tape, and the substrate. A key component of the model is the tack that is formed between the substrate and the slit tape during deposition. A rate-dependent cohesive model is developed to simulate the complex tack response between the two surfaces. Previous papers and presentations by the authors focused on the tack model development and validation; however, this paper focuses on the simulation framework and sensitivity due to the simulation setup (e.g. element type, section definition, mass scaling, damping) and its affect on defect prediction.
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Conference: SAMPE 2019 - Charlotte, NC
Publication Date: 2019/05/20
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