This project supports collaborative research by Dr. Pradeep Rohatgi, Department of Materials Science & Engineering, University of Wisconsin at Milwaukee (UWM), Milwaukee, Wisconsin. The collaborating scientist is Dr. Atef Daoud, Central Metallurgical Research and Development Institute, Helwan, Egypt. They plan to synthesize lightweight lead calcium alloys incorporating microballoons (from flyash, glass or alumina) in the form of composites, for use in automotive and industrial batteries operating under increasingly high temperatures. The grid containing microballoons will be designed to enhance battery life, while decreasing battery weight. The PIs will investigate fundamentals related to solidification synthesis and structure-property relationships in Pb-Ca-microballoon composites. Research will be conducted on the theoretical analysis of transfer microballoons into alloy melts, and solidification of lead-calcium alloy matrices containing microballoons. They will carry out experiments on introduction and transfer of microballoons in the melts of lead-calcium alloys, using mixing, and pressure infiltration processes followed by solidification to create lead-calcium/microballoon composites. Solidified material will be examined by optical and electron microscopy to characterize the distribution of microballoons, interfaces, matrix grain size, dendrite size and microsegregation. Assessment of mechanical and electrical properties will be made to provide a benchmark for optimizing processing parameters. Intellectual Merit: The project will analyze the applicability of the existing knowledge base on synthesis, processing and properties of microcomposites to lead-calcium alloy-microballoon composite materials, and propose new models on synthesis, structure-property relationships in lead calcium alloy based syntactic foams. The characterization of microstructures will help to understand nucleation, growth, microsegregation, particle pushing, and interface formation when solidification of the lead calcium alloy occurs in the small spaces between microballoons. These studies will help to understand the relationships between processing, microstructure and the creep and corrosion behavior of these alloys. The research will elaborate the effect of composition, volume, percent, size and distribution of microballoons on conductivity, modulus strength, creep and corrosion resistance of lead-calcium alloys. Broader Impact: The results are likely to lead to the development of lightweight lead calcium alloys reinforced with microballoons for battery applications. These batteries, which can be produced by companies in the U.S. and Egypt, will lead to weight reduction in vehicles, and especially in trucks. The project will help educate undergraduate and graduate students, including minorities and women, postdoctoral associates, high school students and teachers about lead-calcium alloy-microballoon composites for high temperature battery applications. Instructional modules will be developed for existing courses at UWM and other U.S. institutions. The results will be disseminated through research publications and conferences. The infrastructure developed at UWM for manufacturing of these components will be made available to other researchers. This work on producing high performance syntactic foam components can help to revive the metal casting industry in the U.S.A. This project is being supported under the US-Egypt Joint Fund Program, which provides grants to scientists and engineers in both countries to carry out these cooperative activities.
