Narendra B. Dahotre - US grants

The goal of this collaborative research grant is the development of a novel laser-based surface engineering technique to enhance the ductility of non-crystalline materials, primarily metals. Laser interference patterning will be employed to produce modified regions of periodic lines or dots of localized ultrafine grain structure with residual stresses on the surface of these materials. The major objectives of the research are (i) to identify the thermo-physical effects associated with the interaction of modulated laser intensity during interference patterning and (ii) to characterize the modulated microstructure, crystallization dynamics, and distribution of residual stresses during laser patterning. These objectives will be instrumental in establishing the role of surface modification on enhancing global plasticity of the non-crystalline materials. Finally, a computational model based on the thermo-physical interactions associated with laser interference patterning of non-crystalline material surfaces for tailoring the effects will be developed.

Successful completion of this project on laser interference patterning will significantly advance the state-of-the-art in ductilization of inherently brittle non-crystalline alloys leading to wider acceptance of these materials for advanced structural applications. The research will elucidate the fundamental mechanisms of plasticity enhancement of non-crystalline materials through design of periodic surface structures consisting of original non-crystalline regions and regions of ultrafine grain structure with residual stresses. Through synergistic computational and experimental approach, the research is expected to establish a methodology for design and synthesis of next generation structural materials system. Furthermore, the collaborative project will provide opportunities for students to work on novel and advanced processing methods and materials and will help prepare diverse and capable workforce of next generation global scientists/engineers.

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).

This award supports the renovation and modernization of approximately 2,900 square feet of space within the University of North Texas' (UNT) Center for Advanced Research and Technology (CART), located in the university's Discovery Park (about 4.5 miles north of the main campus). As part of CART, UNT will create a modern, model facility, called the UNT Nanofabrication Analysis and Research Facility (NARF), which is to be an open-access "one-stop-shop" for advanced device fabrication and analysis across multiple length and time scales. The renovations will consolidate currently spatially distributed, advanced characterization and analysis instruments; upgrade the space to include high speed cyber connectivity permitting remote access and control of these instruments; and integrate this space with a clean room and technology incubator.

Intellectual Merit: NARF will use "open system design" architecture to maximize collaboration and shared use of equipment, "integration for fabrication" to maximize entrepreneurial activities characterized by co-location of a clean room and technology incubator, and a "community/school-friendly" setting, where researchers share results and explain their work in real-time or via distance to visitors. The facility will host a unique trio of tools consisting of a dual-beam focused ion beam instrument, a high resolution transmission electron microscope, and a local electrode atom probe, capable of true atomic scale analysis of the structure and chemistry of materials, as well as many other advanced instruments, into direct proximity of one another. NARF will foster fundamental research involving nanoscale characterization and analysis applied to a wide variety of materials systems and devices, and will allow for the first time at UNT, true 3D characterization of the nanoscale structure and composition of specific components and failure sites in semiconductor devices, as well as interfaces in hybrid materials for aerospace, biomedical, and energy-related applications.

Broader Impacts: One of the primary impacts enabled by NARF will be the research training of graduate and undergraduate students, as well as post-docs and external researchers from industry, in the use of sophisticated characterization and analysis equipment. NARF will provide researchers a range of different equipment under one roof and allow them to appreciate the novel research possibilities afforded by these various techniques. Such an impact is not possible if the equipment is isolated and located at geographically scattered locations across the campus, as it is currently.

1134882 Colorado School of Mines; Michael Kaufman
1134873 University of North Texas; Peter Collins

The Center for Advanced Non-Ferrous Structural Alloys will focus on the physical metallurgy of non-ferrous alloys (alloying and processing effects on microstructure, properties and performance) and on the industries that develop, manufacture, and use these alloys. Colorado School of Mines (CSM) and the University of North Texas (UNT) are collaborating to establish the proposed center, with CSM as the lead institution.

The proposed Center aims to establish the industrial support, operational mechanisms, and a prospective research portfolio for a viable research Center that will conduct critical basic and applied physical metallurgy research of direct relevance to the industries that develop, manufacture and use advanced non-ferrous structural alloys. The PIs are proposing the following topical areas: high performance alloys (nickel base super alloys and titanium base alloys), lightweight alloys including aluminum, magnesium (and their composites), and advanced alloys and processes. The PIs will insure that students have the opportunity to work on state-of-the-art projects and to be mentored by both experimental and modeling experts. The management of these focus areas is being modeled after the highly successful Advanced Steel Products and Processing Center at CSM, namely, by having companies designate what portion of their membership fees they wish to have distributed into the three specific focus areas.

The proposed Center has the potential to improve sustainability and profitability of US manufacturing by developing advanced non-ferrous alloys that could reduce energy consumption and pollution in the manufacturing of these alloys. The research would also improve the competitiveness of US manufacturers. Given that the focus of the proposed center will be on the physical metallurgy of structural non-ferrous alloys, the associated programs of study at the two institutions will be reexamined and potentially modified in order to insure that the undergraduate and graduate curricula are consistent with this focus. In other words, both institutions will work to insure that the undergraduate and graduate students receive proper education and training in order for them to be well grounded in fundamental principles of physical metallurgy. As a center interacting with industry, the PIs intend to reach out to local communities to bring their attention to the issues facing this particular industry sector and how the institutions can assist these industries as they compete in these global markets. The center will also insure that diversity is one of the criteria in the selection of both undergraduate and graduate students who are considered for the industry relevant projects.