Novel application of Yttria Stabilized Zirconia as a substrate for thin film CIGS solar cells
Yttria Stabilized Zirconia [YSZ] has a number of qualities that make it attractive as a substrate for fabrication of thin film copper indium gallium diselenide [CIGS] solar cells: these include flexibility, a smooth surface, lack of impurities such as iron and the ability to scale to a roll-to-roll format. As an insulator, YSZ is compatible with monolithic processing and its high temperature capabilities enable high efficiency deposition temperature. Small area [0.41 cm2] CIGS solar cells were fabricated on a YSZ substrate yielding a 17.3% efficient device.
Manufacturing Technology (MATES) II. Task Order 0006: Air Force Technology and Industrial Base Research Sub-Task 07: Future Advances in Electronic Materials and Processes-Flexible Hybrid Electronics
Abstract : This report documents the findings of a study of the U.S. electronics manufacturing industry, including an integrated assessment focused on projected advances in electronics materials and processes and their implications for military aerospace applications. A major goal of the study was to understand trends, manufacturing issues/barriers, enabling technologies, and investment opportunities with significant potential for payoff in the context of future electronics product capabilities, especially for military aerospace applications. While the work covered the U.S. electronics industry in general, it placed special emphasis on flexible hybrid electronics (FHE) as an emerging and promising industry. The analysis addressed latest developments in inorganic and organic materials for specialty applications, including recent developments in 2D materials such as graphene for electronics applications. For both conventional electronics and FHE, the study included a review of materials, manufacturing processes, packaging technologies, design tools, and current and proposed applications, and identification of technology gaps and opportunities for investment. For conventional electronics, it also addressed computational tools for design of resilient electronics for severe environments. For the emerging field of FHE, the report includes estimates of future trends in applications and the technologies that are expected to enable them.
Neutron Residual Stress Measurements on Rail Sections for Different Production Conditions
Rail sectioning with subsequent neutron diffraction experiments has been used to assess residual stresses in the rails. In this study we present the results of neutron stress measurements performed at the NIST Center for Neutron Research (NCNR) on rail sections from rails that were produced under various conditions. Specifically, these are air-cooled, air-cooled and roller-straightened, head-hardened and head-hardened and roller-straightened. More significantly, a head-hardened and roller-straightened rail was also studied after service to elucidate evolution of the service-induced residual stresses. In the latter case both a transverse-cut slice and the central region of a 0.53 m long piece were studied. Measurements on this piece are the first in which triaxial stresses have been determined for an intact rail. Neutron strain measurements with 3×3×3 mm3 spatial resolution were successfully employed for transversally cut slices to verify the difference in the stress state depending on the production process. Although examination of slices allows determination of only two-dimensional stresses in the plane of the slice, additional measurements on obliquely-cut slices, which were also carried out, and utilization of FEM gives the possibility of reconstructing the full triaxial stress distribution. Together, these approaches provide a better understanding of rail fabrication and the possibility of improving the durability and safety of rails in the future.Copyright © 2004 by ASME