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A D V A N C E D M A T E R I A L S & P R O C E S S E S | O C T O B E R 2 0 1 7 2 8 properties are determined by the ele- ments themselves and interactions be- tween dissimilar elements. Thus, even small changes in HEA chemical compo- sition can have a significant effect on the properties. Synthesis of HEA nano- materials by chemical methodologies is complex. However, fabrication of HEA nanomaterials might be easier using high-energy ball milling and laser abla- tion (Fig. 6). WGB technology can benefit from nanomaterial implementation. It is common to mix the brazing material and the additive gap-filler metal in powder form for activated diffu- sion bonding. In powder form, diffu- sion is enhanced due to more atoms being located on the particle sur- face. Enhanced diffusion is even more prominent in nanomaterials, which is the reason they be joined even at room temperature [19] . Nanomaterials have great potential as additive filler materials and brazing materials in WGB technology. Brazing dynamics would be size controlled instead of MPD diffusion-controlled in standard bra- zing practices. In summary, nanobrazing is still in its infancy, but interest is grow- ing. Incorporation of nanobrazing into conventional brazing technologies in- troduces a new horizon for turbine blade and vane repair. Due to the unique “nanopowdering” of filler ma- terials, the metallurgical mechanisms and thermodynamics of nanobrazing are becoming a promising frontier for materials science and the development of innovative applications. ~AM&P For more information: Anming Hu is an assistant professor, Department of Mechanical, Aerospace and Biomedical Engineering, University of Tennessee Knoxville, 1512 Middle Dr., Knoxville, TN 37996, 865.974.5993, ahu3@utk.edu , www.utk.edu. References 1. Y. Sun, et al., Microstructure Evolution of Single Crystal Superalloy DD5 Joints Brazed Using AWS Bni-2 Filler Alloy, Mater. Res. Innov., Vol 18, p 341-346, 2014. 2. X. Huang and W. Miglietti, Wide Gap Braze Repair of Gas Turbine Blades and Vanes - A Review, J. Eng. Gas Turbines and Power, Vol 134, p 10801, 2012. 3. X.S. Zhou, et al., Transient Liquid Phase Bonding of CLAM/CLAM Steels with Ni-Based Amorphous Foil as the Interlayer, Mater Design, Vol 88, p 1321- 1355, 2015. 4. N. Sheng, et al., Transient Li- quid Phase Bonding Single Crystal Superalloys with Orientation Devia- tions: Creep Properties. Metall. Mater. Trans. A, Vol 46A, p 5772-5781, 2015. 5. Y. Ma, et al., Zero-Dimensional to Three-Dimensional Nanojoining: Current Status and Potential Appli- cations, RSC Adv., The Royal Soc. of Chemistry, Vol 6, p 75916-75936, 2016. 6. S. Hausner, S. Weis, and G. Wagner, Joining of Steels at Low Temperatures by Ni Nanoparticles, 11th Intl. Conf. on Brazing, High Temperature Brazing and Diffusion Bonding, Aachen, Germany, Dusseldorf, DVS Media GmbH, p 278- 284, 2016. 7. M.G. Nicholas, Joining Processes: Introduction To Brazing And Diffusion Bonding, Boston, Kluwer Academic Publishers, 1998. 8. J.D. Liu, et al., Effect of Transient Liquid Phase (TLP) Bonding on the Ductility of a Ni-Base Single Crystal Superalloy in a Stress Rupture Test, Mater. Charact., Vol 59, p 68-73, 2008. 9. H.M. Hdz-García, et al., Aging Thermal Treatment in the Inconel 725 Brazed Incorporating Tungsten Nanoparticles, J. Nanomater., p 1-7, 2016. 10. C. Ma, et al., Low Temperature Brazing Nickel with Ag Nanoparticle and Cu-Ag Core-Shell Nanowire Nanopastes, J. Alloy Compd., Vol 721, p 431-439, 2017. 11. H.A. Alarifi, et al., Determina- tion of Complete Melting and Sur- face Premelting Points of Silver Fig. 6 — SEM image of (a) ball-milled Ni-Mn-Cu-Co-Fe high-entropy alloy nanopastes and (b) laser-ablated Ni-Mn-Cu-Co-Fe high-entropy alloy nanopastes. Fig. 5 — Schematic of laser powder deposition for repair applications.