U.S.-Brazil Collaborative Research: Pattern Forming Instabilities in Directional Solidification - Experimental Tests of Non-Steady-State Theory

拟议中的美国-巴西合作研究将使用与金属合金密切相关的一类材料进行实验，以测试最近先进的界面演化非稳态理论。以1965年发现的材料为基础，利用视频显微镜和计算机图像分析技术，观察、提取和分析了界面轮廓和溶质浓度场的相关特征。该项目由纽约市立大学的Herman Cummins和巴西贝洛奥里藏特米纳斯吉拉斯州联邦大学的Oscar Mesquita领导，将使用两个地点可用的设备。第二个目标将是研究平面到细胞分叉的性质，对材料制备和设计有潜在的影响。这项研究用最新的方法解决了一个既有理论意义又有实践意义的问题。在过去的几年里，研究复杂的、非线性的自然问题的能力才得到发展，这为我们的研究开辟了道路。该项目将在相关问题上有经验的美国和巴西调查人员配对，有望取得有价值的成果。＊＊＊

9512708 Cummins The proposed U.S.-Brazil collaborative research will use experiments with a class of materials closely related to metallic alloys to test a recently advanced non-steady-state theory of interface evolution. Based on materials discovered in 1965 but using techniques of videomicroscopy and computerized image analysis, the relevant characteristics of the interface profile and solute concentration field will be observed, extracted, and analyzed. The project, led by Herman Cummins at CUNY in New York and Oscar Mesquita at the Universidade Federal de Minas Gerais in Belo Horizonte, Brazil, will use equipment available at both sites. A second objective will be to investigate the nature of the planar-to-cellular bifurcation, with potential implications for materials preparation and design. The research addresses a question of both theoretical and practical importance using the latest methods. The ability to attack complex, non-linear problems of the nature proposed has only developed in the past few years, opening the way for the proposed research. The project pairs U.S. and Brazilian investigators with experience in related problems, promising valuable results. ***