Discipline: Physics
Subcategory: Physics (not Nanoscience)
Jose Nicasio - Farmingdale State College
Co-Author(s): H. Ilyas, J. Pabla, and J. W. Simonson, Farmingdale State College, Farmingdale, NY J. C. Misuraca, JEOL USA Inc., Peabody, MA
Steel turbines in power plants are susceptible to oxidation in steam-rich environments at high temperatures, which limits the efficiency of electrical power generation [1]. We present the synthesis and basic characterization of high quality single crystals of the Cr-Ni-Al 1 phase [2] in order to find a new material suitable for oxidation-resistant coatings in high temperature applications. By manipulating the amount of nickel in the crystal growth system, we are able to produce crystals as large as 9 x 2 x 2 mm3 to facilitate precise measurement of relevant properties. The crystal structure was solved from single crystal x-ray diffraction data, and the composition was determined by energy-dispersive x-ray spectroscopy. Our crystals have a hardness as determined by Vickers microhardness indentation rivaling that of most high-strength steels as well as low electrical and thermal conductivities, despite a density of only 3.6 g/cm3. These critical properties, as well as excellent resistance to oxidation, make this material ideal for protective coatings on high temperature steels. We suggest future research into more efficient ways to synthesize and deposit the 1 phase on a larger scale.
References: [1] R. J. Campbell, “Increasing the Efficiency of Existing Coal-Fired Power Plants,” CRS Report 7-5700 (2013) R43343.
[2] R. E. Marsh, “Concerning the κ-phase of Al-Cr-Ni,” Acta Cryst. B54 (1998) 925-926
Funder Acknowledgement(s): Acknowledgment is made to the Donors of the American Chemical Society Petroleum Research Fund for support of this research under contract 56764-UNI10. J. E. Nicasio was supported by an NYSED CSTEP Grant, under Contract No. C401633 and by the NSF under the LSAMP program.
Faculty Advisor: J. W. Simonson, jack.simonson@farmingdale.edu
Role: Planning and synthesis of crystals, optimization of synthesis, analysis of single crystal x-ray diffraction data, hardness measurements, electrical conductivity measurements, oxidation resistance measurements, analysis of results.