FY05 HPCRM Annual Report: High-Performance Corrosion-Resistant Iron-Based Amorphous Metal Coatings (open access)

FY05 HPCRM Annual Report: High-Performance Corrosion-Resistant Iron-Based Amorphous Metal Coatings

New corrosion-resistant, iron-based amorphous metals have been identified from published data or developed through combinatorial synthesis, and tested to determine their relative corrosion resistance. Many of these materials can be applied as coatings with advanced thermal spray technology. Two compositions have corrosion resistance superior to wrought nickel-based Alloy C-22 (UNS No. N06022) in some very aggressive environments, including concentrated calcium-chloride brines at elevated temperature. Two Fe-based amorphous metal formulations have been found that appear to have corrosion resistance comparable to, or better than that of Ni-based Alloy C-22, based on breakdown potential and corrosion rate. Both Cr and Mo provide corrosion resistance, B enables glass formation, and Y lowers critical cooling rate (CCR). SAM1651 has yttrium added, and has a nominal critical cooling rate of only 80 Kelvin per second, while SAM2X7 (similar to SAM2X5) has no yttrium, and a relatively high critical cooling rate of 610 Kelvin per second. Both amorphous metal formulations have strengths and weaknesses. SAM1651 (yttrium added) has a low critical cooling rate (CCR), which enables it to be rendered as a completely amorphous thermal spray coating. Unfortunately, it is relatively difficult to atomize, with powders being irregular in shape. This causes the powder to be …
Date: September 20, 2007
Creator: Farmer, J.; Choi, J.; Haslam, J.; Day, S.; Yang, N.; Headley, T. et al.
System: The UNT Digital Library
FY05 LDRD Final Report, A Revolution in Biological Imaging (open access)

FY05 LDRD Final Report, A Revolution in Biological Imaging

X-ray free-electron lasers (XFELs) are currently under development and will provide a peak brightness more than 10 orders of magnitude higher than modern synchrotrons. The goal of this project was to perform the fundamental research to evaluate the possibility of harnessing these unique x-ray sources to image single biological particles and molecules at atomic resolution. Using a combination of computational modeling and experimental verification where possible, they showed that it should indeed be possible to record coherent scattering patterns from single molecules with pulses that are shorter than the timescales for the degradation of the structure due to the interaction with those pulses. They used these models to determine the effectiveness of strategies to allow imaging using longer XFEL pulses and to design validation experiments to be carried out at interim ultrafast sources. They also developed and demonstrated methods to recover three-dimensional (3D) images from coherent diffraction patterns, similar to those expected from XFELs. The images of micron-sized test objects are the highest-resolution 3D images of any noncrystalline material ever formed with x-rays. The project resulted in 14 publications in peer-reviewed journals and four records of invention.
Date: January 20, 2006
Creator: Chapman, H. N.; Bajt, S.; Balhorn, R.; Barty, A.; Barsky, D.; Bogan, M. et al.
System: The UNT Digital Library