CAREER: Integrated Approach To Superplastic Forming of Advanced Materials: Mechanics-Materials-Manufacturing Linkage

该学院早期职业发展计划提出了一种整合力学，材料和制造概念的新方法，以优化超塑性成形（SPF）工艺并推进其工业应用。该项目的主要研究目标是：(1)提高目前SPF过程中材料变形和失效的预测能力；(2)设计最佳成形工艺以提高生产率。为了实现第一个研究目标，将开发精确的多轴和基于微观结构的变形和破坏本构模型，并将其纳入通用有限元程序。建模框架将基于基于微观结构的超应力函数、动态各向异性屈服面和内部变量的大粘塑性变形。这些模型将通过详细的机械测试进行校准和验证，包括多轴实验，以及与国家实验室合作的先进微观结构表征技术。第二个研究目标将通过开发最佳的成形压力分布来实现，从而减少成形时间并保持成形部件的完整性，并通过使用搅拌摩擦加工（FSP）来细化超塑性板材的初始微观结构。这项研究还将包括详细的SPF后分析，这是之前SPF研究中被忽视的一个问题。结果是一个综合的方法，其中包括实验程序，分析和数值模型，可用于优化各种超塑性合金的SPF。该项目的重点将放在商用镁合金上，因为它们具有独特的性能，而且最近人们对镁合金的兴趣越来越大，尤其是汽车工业。CAREER项目的教育计划概述了以下工作：(1)让幼儿接触到工程专业令人兴奋的可能性，激发他们的想象力和好奇心；(2)帮助工科新生更多地了解工程学科知识，提高留校率；(3)鼓励工科学生参与第1和第2项所提到的活动，并确保学生的参与包括女生和少数族裔学生在内的所有方面；(4)引入符合ABET新要求的现代本科和研究生课程，特别是将机械和材料的进步融入制造业的需要。教育部分将通过投资于青年和加强和促进国家唯一的儿童博物馆，对国家的福利产生直接影响。职业发展计划包括一个管理计划，以确保实现目标。它涉及一个由多学科人员组成的咨询委员会，提供技术咨询，促进结果的传播，并确保调查结果的曝光。研究活动的成功将促进SPF的广泛工业利用。这将对社会产生积极影响，并将导致更便宜，更安全，更环保的产品。

This Faculty Early Career (CAREER) development plan presents a novel approach that integrates mechanics, materials and manufacturing concepts to optimize the superplastic forming (SPF) process and advance its industrial utilization. The principal research goals of this project are: (1) to improve the current predictive capabilities of material deformation and failure during SPF and (2) to devise optimum forming practices to increase production rate. To achieve the first research goal, accurate multiaxial and microstructure-based constitutive models of deformation and failure will be developed and incorporated into a general purpose FE code. The modeling framework will be based on large viscoplastic deformation with a microstructure-based overstress function, a dynamic anisotropic yield surface, and internal variables. The models will be calibrated and validated using detailed mechanical tests, including multiaxial experiments, and advanced microstructural characterization techniques in collaboration with a National laboratory. The second research goal will be achieved by developing optimum forming pressure profiles that can reduce the forming time and maintain the integrity of the formed part, and by refining the initial microstructure of the superplastic sheet using friction stir processing (FSP). The research will also include a detailed post SPF analysis, an issue that has been neglected in previous SPF studies. The outcome is a comprehensive methodology, which involves experimental procedures, analytical and numerical models that can be used to optimize SPF of various superplastic alloys. The focus of this project will be on commercial magnesium alloys because of their unique properties and the recent increased interest in Mg alloys, especially from the automotive industries.The education plan in this CAREER project outlines efforts to: (1) expose young children to the exciting possibilities of the engineering profession and inspire their imagination and curiosity; (2) help freshmen engineering students learn more about engineering disciplines and help improve retention rate; (3) encourage engineering students to be involved in the activities mentioned in 1 and 2, and ensure that student involvement includes all facets of the student population including female and minority students; and, (4) introduce modern undergraduate and graduate courses which meet the new ABET requirements, in particular, the need to integrate advances in mechanics and materials into manufacturing. The educational component will have a direct impact on the welfare of the State by investing in the youth and strengthening and promoting the only children's museum in the State. The CAREER development program includes a management plan to ensure achieving the objectives. It involves an advisory committee consisting of multidisciplinary individuals to offer technical advice, facilitate dissemination of the results and ensure exposure of the findings. The success of the research activities will advance the widespread industrial utilization of SPF. This will have a positive impact on society and will lead to cheaper, safer and environmentally friendly products.