An Investigation of the Thermomechanical Behavior of Fiber Reinforced Thermoset Composite Parts

对纤维增强复合材料零件的热力学行为进行了研究。该项目的目标是继续研究纤维增强热固性零件的热力学行为的建模、分析和过程模拟。这样的研究将增加对收缩、翘曲和表面波纹背后的现象和物理的理解。该项目将分为两个部分：实验部分和计算机建模部分。实验方面的研究涉及热机械材料的性能表征。本文研究了固化程度对凝固过程中弹性常数和收缩率的影响。在项目的第二部分，将介绍由于固化而导致的收缩，并将开发材料张量的本构模型，并将其应用于现有的有限元计算机模拟中，模拟在薄厚纤维增强热固性部件成型过程中发生的热力过程。仿真考虑了在现实工业加工条件下成型的复杂几何形状零件。了解塑料的热力学行为，并能够预测填充模式，纤维取向，固化过程中的温度场，残余应力，空隙和裂缝，收缩，零件实际制造前的翘曲和表面波纹导致更高的零件质量，并消除了在零件和模具设计的早期阶段完成的一些昂贵和耗时的任务。

An investigation of the thermomechanical behavior of fiber reinforced composite parts will be conducted. The objective of the project is to continue research in modeling, analysis and process simulation of the thermomechanical behavior of fiber reinforced thermoset parts. Such a study will increase the understanding of the phenomena and the physics behind shrinkage, warpage and surface waviness of reinforced plastic parts. The project will be divided into two portions: and experimental and a computer modeling portion. The experimental aspect of the research deals with thermomechanical material properties characterization. Here, the effect that degree of cure has on the elastic constants and on shrinkage during solidification will be studied. In the second portion of the project the shrinkage due to cure will be introduced and a constitutive model for the material tensor will be developed and implemented into existing finite element computer simulations of the thermomechanical processes that take place during molding of thin and thick fiber reinforced thermoset parts. The simulation considers parts of complex geometry molded under realistic industrial processing conditions. Understanding the thermomechanical behavior of plastics and being able to predict filling patterns, fiber orientation, temperature fields during cure, residual stresses, voids and cracks, shrinkage, warpage and surface waviness before a part is actually manufactured leads to higher part quality and eliminates some of the expensive and time consuming tasks done in the early stages of part and mold design.