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

该奖项提供资金，允许特伦斯G。 兰登，材料科学系，大学 南加州（USC），与何哲博士合作 Kim，韩国高等物理研究所物理学教授 科学和技术（KAIST），为期24个月，一个计划 合作研究非核武器的应用， 破坏性技术的调查 超塑性中的空穴现象 他们以前的研究 在NSF资助号INT-8803709下得到支持。 这些 科学家及其研究小组的成员将 继续通过使用 破坏性超塑性试验，在南加州大学，与非- 破坏性超声速度和光声 光谱学（PAS）在KAIST。 （1）使用 金相，在USC验证PAS结果， KAIST，（2）扩大其程序，包括较低的 延伸，和（3）扩大其调查， 包括金属以外材料。 超塑性是指某些金属 通常表现出异常高的无颈部伸长， 超过1，000%，当在升高的张力下拉伸时， 温度 这一现象具有相当大的 商业利益，因为许多潜在的 在钣金成形中的应用。 的一个主要问题 超塑性是内部的形核和生长 蛀牙 这些空洞可能导致严重的 的后成形性能的退化， 材料 因此，重要的是估计 空腔体积，非破坏性，并验证 这些估计使用金相技术。 的 合作者都是备受尊敬的科学家， 这项研究的领域。 他们过去的合作 对文献做出了重大贡献 这一领域。 美国科学家将受益于 使用无损检测设施， 在KAIST有，但在USC没有。 这个项目是 与美国的目标相关-韩国合作社 科学计划，旨在提高 美国和韩国科学家之间的合作， 工程师通过科学交流 信息、想法、技能和技术， 在互惠互利的问题上进行合作。 韩国 参与该项目得到了韩国的支持 科学和工程基金会。

This award provides funds to permit Dr. Terence G. Langdon, Department of Materials Science, 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 non- destructive techniques to the investigation of cavitation in superplasticity. Their research formerly was supported under NSF Grant No. INT-8803709. These scientists and members of their research groups will continue their collaboration through the use of destructive superplastic testing, at USC, with non- destructive ultrasonic velocity and photoacoustic spectroscopy (PAS) at KAIST. They will (1) use metallography, at USC to verify PAS results obtained at KAIST, (2) extent their procedures to include lower elongations, and (3) expand their investigations to include materials other than metals. 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 commercial interest because of the many 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. It is important, therefore, to estimate the volume of cavities, non-destructively, and to verify these estimates using metallographic techniques. The collaborators are highly respected scientists in the field of this research. Their past collaboration has resulted in significant contributions to the literature of this field. The U.S. scientist will benefit from access to facilities for non-destructive testing, available at KAIST, but not at USC. This project is relevant to the objectives of the U.S.-Korea Cooperative Science Program which seeks to increase the level of cooperation between U.S. and Korean 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).