U.S.-Korea Cooperative Research: The Application of Non- Destructive Techniques to Investigate Cavitation in Superplasticity

该提案要求获得资金，以允许南加州大学(USC)材料科学系Terence G.Langdon博士与韩国高级科学技术研究所(KAIST)物理学教授Ho Chul Kim博士开展为期24个月的合作研究计划，研究应用无损技术研究超塑性中的空化现象。合作者将利用KAIST的优良设施对美国检测实验室提供的样品进行无损检测。南加州大学没有KAIST的这类设施。超塑性是指某些金属在高温拉伸时表现出极高的无颈伸长率的能力，通常超过1000%。这一现象具有相当大的商业价值，因为它在板材成形中有任何潜在的应用。超塑性的一个主要问题是内部空洞的形核和长大。这些空洞可能会导致材料的后成形性能显著降低。合作者将尝试获得有关空洞大小的间接信息，作为标本历史和测试程序的函数。他们还将尝试将KAIST的无损检测结果与南加州大学的平行光学检查相关联。合作者是这一研究领域备受尊敬的科学家。本项目将使他们能够将自己的才华和兴趣结合起来，实现互利共赢。该项目与美韩合作科学计划的目标相关，该计划旨在通过交流科学信息、想法、技能和技术以及通过在互利问题上的合作来提高美国和韩国科学家和工程师之间的合作水平。韩国参与该项目得到了韩国科学与工程基金会(KOSEF)的支持。

This proposal requests funds to permit Dr. Terence G. Langdon, Materials Science Department, University of Southern California (USC), to pursue with Dr. Ho Chul Kim, Professor of Physics, Korea Advanced Institute of Science and Technology (KAIST), for 24 months, a program of cooperative research on the application of nondestructive techniques to investigate cavitation in superplasticity. The collaborators will use the excellent facilities at KAIST to perform nondestructive testing of samples provided by the testing laboratory in the United States. Facilities of the type at KAIST are not available at USC. Superplasticity refers to the ability of some metals to exhibit exceptionally high neck-free elongations, often in excess of 1,000%, when pulled in tension at elevated temperatures. This phenomenon is of considerable commerial interest because of the any potential applications in sheet-metal forming. A major problem in superplasticity is the nucleation and growth of internal cavities. These cavities may lead to a significant degradation of the post-forming properties of the material. The collaborators will attempt to obtain indirect information on cavity size as a function of both specimen history and testing procedures. They also will attempt to correlate results of nondestructive testing at KAIST with parallel optical examination at USC. The collaborators are highly respected scientists in the field of this research. The present project will allow them to combine their talents and interests for mutual benefit. This project is relevant to the objectives of the U.S.-Korea Cooperative Science Program which seeks to increase the level of cooperative between U.S. and Korea scientists and engineers through the exchange of scientific information, ideas, skills, and techniques and through collaboration on problems of mutual benefit. Korean participation in the project is supported by the Korea Science and Engineering Foundation (KOSEF).