NSF-Europe: The Mechanisms of Grain Refinement in HCP Metals and Alloys with Severe Plastic Deformation Leading to Nanoscale Microstructures

NSF-Europe：HCP 金属和合金中晶粒细化的机制，严重塑性变形导致纳米级微观结构

• 批准号: 0501605
• 负责人: Michael Kassner
• 金额: --
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-09-01 至 2008-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0501605&HistoricalAwards=false
• 关键词: NSF; Europe; Mechanisms; Grain; Refinement

This grant supports a collaborative research program between the University of Southern California (USC) and the Consejo Superior de Investigaciones Cientificas (CSIC) Centro Nacional de Investigaciones Metalurgicas (CENIM), on Madrid, Spain. CENIM has received a three-year grant from the Spanish Ministry of Science and Technology for "Optimization of the Mechanical Behavior of Light Al and Mg Based alloys for the Transportation Industry by Severe Plastic Deformation." The NSF grant provides funding for USC in a complementary area to the Spanish grant. The Spanish research explores severe plastic deformation using rolling of Ti and Zr alloys as a means to produce nanoscale grain-size alloys. Their objective is to create a new class of economical high-strength, light alloys. The US team looks at pure light metals that are a basis for the alloys studied at CENIM. Two essential aspects addressed by the study at USC are (a) the characterization of the evolution of microstructure of light HCP metals and Al single crystals during intense plastic deformation in tension, equal-channel angular pressing, and rolling leading to the formation of a nanocrystalline structure and (b) dynamic restoration mechanisms leading to the nanostructure. The former delineates a specific issue that has not been sufficiently addressed by the scientific community for HCP metals and for single crystals of any structure. The technical community has been empirical in its quest to produce very fine-grain alloys of commercial value. The basic USC effort underpins the adhesive roll-bonding technique centered in Madrid. Adhesive roll-bonding is a technique that may improve present capability to create submicron microstructures by increasing the fraction of subgrain boundary facets that become high angle boundaries and could result in reduced processing costs as compared to equal-channel angular pressing. A primary objective of the grant is student participation in this international program. The program will look for graduate students from underrepresented groups. Graduate students, postdoctoral scholars, and faculty will participate in exchanges on a long-term basis (three months to two years) between the institutions. The collaborative program is complementary in scope, synergistic and, due to a past record of collaboration, highly likely to succeed. Dr. Maria-Teresa Perez-Prado of CENIM and also a Research Assistant Professor at USC is a vital participant in this project. Undergraduates will participate in the program both in the summer and as part of a formal Senior Project. This research will be integrated into the USC Aerospace and Mechanical Engineering courses, AME 560, Fracture and Fatigue of Materials. An additional broad impact feature is the potential for developing an inexpensive and versatile metal-forming technique to produce high strength and high toughness nanoscale light alloys.

该补助金支持南加州大学（USC）和西班牙马德里的科学研究上级委员会（CSIC）国家气象研究中心（CENIM）之间的合作研究计划。CENIM获得了西班牙科学技术部的一项为期三年的资助，用于“通过剧烈塑性变形优化交通运输行业轻铝和镁基合金的机械行为”。“NSF赠款为南加州大学提供西班牙赠款的补充领域的资金。西班牙的研究探索了使用钛和锆合金的轧制作为生产纳米级晶粒尺寸合金的手段的严重塑性变形。他们的目标是创造一种新的经济型高强度轻合金。美国研究小组着眼于纯轻金属，这是CENIM研究合金的基础。在南加州大学的研究所解决的两个重要方面是（a）的微观结构的演变轻HCP金属和铝单晶在紧张，等通道角挤压，并导致形成纳米晶结构和（B）动态恢复机制导致的纳米结构的强烈塑性变形的表征。前者描述了一个尚未被HCP金属和任何结构的单晶科学界充分解决的具体问题。技术界一直在寻求生产具有商业价值的非常细晶粒的合金。南加州大学的基本努力巩固了以马德里为中心的粘合剂辊压粘合技术。粘合剂辊压结合是一种技术，其可以通过增加变成高角度边界的亚晶粒边界刻面的分数来改善产生亚微米微结构的现有能力，并且与等通道角挤压相比可以导致降低的加工成本。补助金的主要目标是学生参与这个国际计划。该计划将从代表性不足的群体中寻找研究生。研究生、博士后学者和教师将参加机构之间的长期交流（3个月至2年）。合作计划在范围上是互补的，协同的，并且由于过去的合作记录，很有可能成功。CENIM的Maria-Teresa Perez-Prado博士也是南加州大学的研究助理教授，是该项目的重要参与者。本科生将在夏季参加该计划，并作为正式的高级项目的一部分。这项研究将被整合到南加州大学航空航天和机械工程课程，AME 560，材料的断裂和疲劳。 另一个广泛的影响特点是开发一种廉价和通用的金属成形技术，以生产高强度和高韧性的纳米级轻合金的潜力。