CAREER: Faculty Early Career Development Program

阿鲁达9702884 该提案的研究内容涉及聚合物的实验测试、表征和本构建模。 半结晶聚合物的应变速率和温度依赖性行为没有很好地表征，也没有完全理解。 现有的半结晶聚合物模型尚未开发出合理的实验范围，以验证实际的材料性能。 这项工作有许多技术上重要的应用，聚合物性能和部件性能之间的关系是当今主要的工程挑战之一。 本提案的PI在设计、实施和 机械测试分析和 聚合物的传统材料科学表征方法。 PI还成功地开发了基于内部变量的无定形（玻璃态和橡胶态）聚合物的本构模型，可以准确地预测它们的三维响应。 拟议的工作涉及广泛的力学测试和材料特性的半结晶聚丙烯与变形的实验观察结果的物理机制。 而且这 研究 将涉及内部 可变 基于本构模型的应变速率和温度依赖行为的半结晶聚丙烯。 这项工作的目标是一个模型，准确地预测实验数据。 拟议研究的具体目标是：（i）通过机械测试和表征，了解聚丙烯在一定应变速率和温度范围内的重要和突出的变形机制，（ii）通过对单轴压缩中各向同性试样的测试，确定聚丙烯的变形依赖性状态，平面应变压缩和拉伸，（iii）研究结构随应变的演化并量化结构状态，（iv）开发基于内部变量的变形响应的三维本构模型，以及（v）通过用户定义的材料选项将该模型实施到商业上可获得的有限元包中以进行验证。 教学部分是对中学女生的宣传，旨在培养对数学和科学职业的持续兴趣。 计划中的活动针对的是处于教育过程中关键时刻的女孩，她们开始开始认为自己不再擅长数学和科学。 在中学，她们被反对女性从事数学和科学职业的影响所包围。 女孩在青春期未能继续选修数学和科学课程，这使她们很快转向非技术学术道路。 为了在青春期对自己的数学和科学能力充满信心，女孩需要更多的鼓励，继续选择高等数学和科学课程。 他们需要了解依赖于坚实的数学和科学教育的许多不同的职业机会。 要成为对工程职业感兴趣的女性，女孩需要看到女性在工程职业中取得成功。 他们需要从女性工程师那里听到，当女性做出职业选择时，她们发现工程学的哪些方面很吸引人。 他们需要从对这一主题充满热情的女性那里学习工程原理。 PI计划开发、实施和评估一个工程职业模块，让女教师和女大学生参与中学女生的工程教学。 该模块涉及PI前往密歇根州华盛顿县的中学， 全国各大学妇女的研究工作。 它将为项目中的女孩提供通过互联网与这些妇女互动的机会 和电子邮件。 该计划中的女孩还将参与设计项目，利用动手，团队学习策略，对女孩有吸引力。 将强调解决社会问题的重要性以及数学和科学课程对未来职业机会的有用性。 这项推广活动的传播计划包括： 本科女性 从 的 学院 密歇根大学的工程学院开发了各种工程学科的类似模块，并将打包模块发送给大学的女工程师 全国的大学。

Arruda 9702884 The research component of this proposal is concerned with experimental testing, characterization and constitutive modeling of polymers. The strain rate and temperature dependent behavior of semicrystalline polymers is not well characterized nor completely understood. Existing models for semicrystalline polymers have not been developed in conjunction with a reasonable range of experiments for verification of actual material performance. There are many technologically important applications for this work, the relationship between polymer properties and part performance is one of today's major engineering challenges. The PI of this proposal is experienced in the design, implementation and analysis of mechanical tests and in traditional materials science characterization methods for polymers. The PI has also successfully developed internal variable based constitutive models of amorphous (glassy and rubbery) polymers that accurately predict their three dimensional response. The proposed work involves extensive mechanical testing and material characterization of semicrystalline polypropylene to relate the physical mechanisms associated with deformation to experimentally observed results. Also, this research will involve internal variable based constitutive modeling of the strain rate and temperature dependent behavior of semi-crystalline polypropylene. The goal of this work is a model that accurately predicts the experimental data. The specific objectives of the proposed study are: (i) to gain an understanding of the important and prominent deformation mechanisms in polypropylene over a range of strain rates and temperatures through mechanical testing and characterization, (ii) to determine the state of deformation dependence of polypropylene through tests on isotropic specimens in uniaxial compression, plane strain compression and tens ion, (iii) to study the evolution of structure with straining and quantifying structural state, (iv) to develop an internal variable based, three dimensional constitutive model of the deformation response and (v) to implement the model into a commercially available finite element package via a user defined material option for verification. The teaching component is outreach to middle school girls designed to foster continued interest in math and science based careers. The planned activity targets girls at a critical time in their education process when they begin to start believing they no longer are good at math and science. In middle school they are surrounded by influences against math and ;science careers for women. Girls fail to continue to elect math and science courses in adolescence which quickly steers them towards non-technical academic paths. To emerge from adolescence with confidence in their math and science abilities, girls need more encouragement to continue to elect advanced math and science courses. They need to understand the many varied career opportunities that rely on a solid math and science education. To become women with an interest in engineering careers, girls need to see women succeeding in their engineering careers. They need to hear from women engineers about the aspects of engineering they found appealing when the women made their career choices. And they need to learn engineering principles from women who are enthusiastic about the subject. The PI plans to develop, implement and evaluate an engineering career module that engages women faculty and undergraduates in teaching middle school girls about engineering. The module involves the PI going to middle schools in Washtenaw County, MI to highlight the research work of women at universities nationwide. It will provide opportunities for girls in the program to interact with these women through the internet and email. The girls in the program will also engage in design projects utilizing hands-on, team learning strategies that are attractive to girls. The importance of problem solving in society and the usefulness of math and science classes for future career opportunities will be stressed. Dissemination plans for this outreach activity include enlisting undergraduate women from the College of Engineering at Michigan to develop similar modules in various engineering disciplines, and sending the packaged modules to women engineering faculty at colleges and universities nationwide.