GOALI: Collaborative Research: Integrated Computational-Experimental Program for Ductility and Failure in Cast Aluminum Alloys

GOALI：协作研究：铸造铝合金延展性和失效的综合计算实验计划

• 批准号: 0308666
• 负责人: Somnath Ghosh
• 金额: --
• 依托单位: Ohio State University Research Foundation -DO NOT USE
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2003
• 资助国家: 美国
• 起止时间: 2003-07-15 至 2008-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0308666&HistoricalAwards=false
• 关键词: GOALI; Collaborative; Research; Integrated; Computational

Integrated computational- experimental program for ductility and failure in cast aluminum alloys Somnath Ghosh, Bhaskar Majumdar and Steve Harris Today's The automotive industry is faced with major challenge of improvedmustis faced with major challenges to improve performance to and reduce weight ratio in order to meet lofty fuel efficiency and emissions standards at low cost. Improved mAs designs become more complex and the power output requirements increase, the practical limits of their ductility and ultimate strength are being reached.,. which Scrapped parts and downtime can cost a manufacturer millions of dollars in terms of scrapped parts and downtime. Compounding The proposed Industry-University Collaborative GOALI research is aimed at addressing thisese issues for meeting goals of materials with high ductility, ultimate strength and strength at low cost. It will build a collaborative relation between the Ohio State University (PI), New Mexico Institute of Technology and Ford Research Laboratory (industry partner) to launch an integrated experimental-computational research program. The program will augment a major thrust area at FRLord called Virtual Aluminum Casting or VAC that is targeted to (a) reduce product development time (b), improve quality and performance, and reduce scrap and (c) improve performance and lower weight, and (d) reduce costs. and cycle time. The proposed program will develop a system of experimentally validated adaptive multiple scale computational models for predicting localization and ductile fracture of cast Al-Si components from microstructural information and process conditions. The models will simulate the evolution of microstructural features such as voids and secondary phases into incipient cracks and determine how the loss of ductilityductile failure depends on alloy properties and on the , distributions and interactions of different phases in the microstructure. The mechanics of particle fracture, interface decohesion, matrix rupture and damage percolation through the dendritic network will be studied. The role of porosity size and distribution on failure will also be investigated. Various dDevelopmental modules will include: (i) Quantitative metallography using SEM, and orientation imaging microscopy (OIM), and microstructural characterization to identify and characterize critical microstructure features that control important material response; (ii) Mechanical tests accompanied bywith in-situ SEM and fracture surface observations, computer imaging and microstructural characterization observation to generate strain fields and to provide understanding of critical mechanisms in the failure process; (iii) Neutron diffraction measurements and Raman microprobe techniques for microstress evolution and probabilistic strength estimation of particles; (iv) Development of an adaptive multi-level model for multiple scale analysis to predict the failure process as a phenomenon of multi-scale incidence and propagation of cracks; (v) Development of image-based microstructural Voronoi Cell finite element model for efficient and accurate analysis of plastic deformation, strain localization and damage evolution in nonuniform heterogeneous microstructures; and (vi) Incorporation of a probabilistic analysis framework to account for the effect of input variabilities on ductility and failure. The major intellectual merit of the proposed research is in its innovative blend of state state-of of-the the-art computational tools andwith experimental methods to advance provide a comprehensive analysis tool and design methodology for advanced metallic materialscast metals to increase their effective utilization. The uniqueness of this approach is in the broad attack on the problem: (a) iIntroduction of adaptive hierarchical and multi-scale computational models, incorporating image-based microstructural models to depict the percolation of damage at different length scales;. T (b) he iIncorporation of detailed microstructures at the critical regions of evolving damage and localization is possible through the efficient and accurate Voronoi Cell finite elementFE model, being developed by the PI.; and (c) Robust validation of the models through rigorous feedback from multi-scale experiments and material characterization by using in-situ SEM, orientation imaging microscopy (OIM), in-situ neutron diffraction and Raman microprobe. To the best knowledge of the investigators, there is a lack of such a necessary comprehensive approach to the understanding of response and failure characteristics of complex cast microstructures. The program, upon completion, is expected towill provide a good understanding of stress and strain evolution ofin the the complex phases in cast Al, their strength levels, and damage initiation and percolation through the network of brittle, ductile and porous phases. The broader impact of the program will occur on two fronts. front, the It will reach beyond the automotive industry to aid the entire casting industry, where significant gains in alloying and solidification technology is are often stymied by unknowns regardingnot knowing how variability in material and process parameters affect damage tolerance and ductility. The methodology will allow industry be able to leapfrog thepresent technology and use these lightweight allows into in new safety -critical applications, armed with the knowledge that ductility and fracture can now be predicted with a reasonable degree of confidence. The second front will be oGraduate students will intern at FRL every summer and NMT students will have access to equipment at the national labs. As a consequence of the university-industry collaboration collaboration, students in this program will have a strong interaction with and mentorship from industrial researchers . There will also be student interaction with researchers at Sandia National Laboratory. researchers. In addition, the national laboratories will be involved in the experimental component of the work.

今天的汽车工业面临着改进汽车的重大挑战，面临着提高性能和降低重量比的重大挑战，以便以低成本达到更高的燃油效率和排放标准。改进的mAs设计变得更加复杂，功率输出要求增加，其延展性和极限强度的实际极限正在达到。报废的零件和停机时间会给制造商造成数百万美元的损失。拟议的产学研合作目标（Industry-University Collaborative goal）研究旨在解决这些问题，以满足材料的高延展性、极限强度和低成本强度的目标。它将在俄亥俄州立大学（PI）、新墨西哥理工学院和福特研究实验室（行业合作伙伴）之间建立合作关系，启动一个综合实验-计算研究项目。该项目将增加FRLord的一个主要推力领域，称为虚拟铝铸造（VAC），其目标是(a)缩短产品开发时间(b)提高质量和性能，减少废料；(c)提高性能和降低重量；(d)降低成本。还有循环时间。该计划将开发一个经过实验验证的自适应多尺度计算模型系统，用于根据微观组织信息和工艺条件预测铸造Al-Si部件的局部化和韧性断裂。这些模型将模拟孔洞和次生相等微观组织特征向初始裂纹的演变，并确定塑性破坏的损失如何取决于合金性能以及微观组织中不同相的分布和相互作用。研究了枝晶网络中颗粒断裂、界面脱黏、基体断裂和损伤渗透的机理。孔隙度的大小和分布对破坏的作用也将被研究。各种开发模块将包括：(i)使用SEM和取向成像显微镜（OIM）的定量金相学，以及微观结构表征，以识别和表征控制重要材料响应的关键微观结构特征；（二）进行机械试验，同时进行现场扫描电镜和断裂面观察、计算机成像和微观结构特征观察，以产生应变场，并了解破坏过程中的关键机制；中子衍射测量和拉曼微探针技术用于微应力演化和粒子的概率强度估计；（iv）发展多尺度分析的自适应多级模型，以预测作为裂纹多尺度发生和扩展现象的破坏过程；开发基于图像的微观结构Voronoi Cell有限元素模型，以便有效和准确地分析非均匀非均质微观结构中的塑性变形、应变局部化和损伤演变；纳入一个概率分析框架，以解释投入变数对延性和失效的影响。所提出的研究的主要知识价值在于其创新地融合了最先进的计算工具和实验方法，为先进的金属材料（铸造金属）提供了全面的分析工具和设计方法，以提高其有效利用率。该方法的独特之处在于对问题的广泛攻击：(a)引入自适应分层和多尺度计算模型，结合基于图像的微观结构模型来描述不同长度尺度下的损伤渗透；T (b) i通过PI正在开发的高效、准确的Voronoi Cell有限元模型，可以在演化损伤和局部化的关键区域纳入详细的微观结构；(c)通过多尺度实验的严格反馈和原位SEM、取向成像显微镜（OIM）、原位中子衍射和拉曼微探针的材料表征，对模型进行了鲁棒验证。据研究人员所知，目前还缺乏这样一种必要的综合方法来理解复杂铸造微观组织的响应和破坏特征。该程序完成后，预计将提供一个很好的理解在铸铝复杂相的应力和应变演变，它们的强度水平，以及通过脆性，韧性和多孔相网络的损伤引发和渗透。该计划将在两个方面产生更广泛的影响。首先，它将超越汽车行业，帮助整个铸造行业，在合金和凝固技术的重大进展往往是由于不知道材料和工艺参数的可变性如何影响损伤容限和延展性的未知因素而受到阻碍。该方法将使行业能够超越现有技术，将这些轻量化allow用于新的安全关键应用中，并且现在可以合理程度地预测延展性和断裂。研究生每年夏天将在FRL实习，NMT学生将有机会使用国家实验室的设备。由于大学与行业的合作，该项目的学生将与行业研究人员有很强的互动和指导。学生还将与桑迪亚国家实验室的研究人员进行互动。研究人员。此外，国家实验室将参与这项工作的实验部分。