Evaluation of Cu-Ni-Based Alloys for Thermoelectric Energy Conversion

Abstract:

The recent revitalization of Ioffe plots (entropy conductivity versus electrical conductivity) reminds us that Isotan (Cu55Ni44Mn1) is an outstanding thermoelectric material with a power factor of up to 60 W cm^-1 K^-2 at a specific electrical conductivity of almost 20,000 S cm^-1 at elevated temperature. Even though, Isotan is widely used in thermoelements for temperature measurement, its high open-circuited thermal conductivity of approximately 70 W cm^-1 K^-2 [1] hindered further research as a promising thermoelectric material. Isotan was chosen as a starting composition. Influence of partial substitution of Cu and Ni with heavy elements (Sn,W) on the thermoelectric properties was studied. The alloys were fabricated by arc-melting and microstructurally characterized for grain size and elemental composition by scanning electron microscope (SEM) combined with energy-dispersive X-ray (EDXS). Lattice symmetry and parameters were estimated by X-ray diffraction (XRD). Functional properties as Seebeck coefficient, electrical conductivity and power factor were used to evaluate the thermoelectric performance.

• Periodical: Materials Science Forum (Volume 1016)
• Pages: 107-112
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.1016.107
• Online since: January 2021
• Authors: Timon Steinhoff, Mario Wolf, Florian Nürnberger, Gregory Gerstein, Armin Feldhoff*
• Keywords: Cu-Ni Based Alloys, Microstructure, Power Factor, Thermoelectrics

References

[1] M. Wolf, R. Hinterding, A. Feldhoff, High Power Factor vs. High zT-A Review of Thermo­ electric Materials for High­Temperature Application, Entropy 21 (2019) 1058.

DOI: 10.3390/e21111058

[2] J. De Boor, C. Stiewe, P. Ziolkowski, T. Dasgupta, G. Karpinski, E. Lenz, F. Edler, E. Müller, High­Temperature Measurement of Seebeck Coefficient and Electrical Conductivity, Journal of Electronic Materials 42 (2013) 1711­1718.

DOI: 10.1007/s11664-012-2404-z

[3] J. Fairbanks, Thermoelectrics: The New Green Automotive Technology: Automotive Thermo­ electric Generators and HVAC, U.S. Department of Energy, Washington D.C. 14.­18.05.(2012).

[4] J. He, T. M. Tritt, Advances in Thermoelectric Materials Research: Looking Back and Moving Forward, Science 357 (2017) 6358.

DOI: 10.1126/science.aak9997

[5] H. U. Fuchs, The Dynamics of Heat: a Unified Approach to Thermodynamics and Heat Transfer, Springer Science and Business Media (2010).

[6] A. Feldhoff, Thermoelectric Material Tensor Derived from the Onsager-de Groot-Callen Model, Energy Harvesting and Systems 2 (2015) 517.

DOI: 10.1515/ehs-2014-0040

[7] M. Bittner, N. Kanas, R. Hinterding, F. Steinbach, J. Räthel, M. Schrade, K. Wiik, M. A. Einarsrud, A. Feldhoff, A Comprehensive Study on Improved Power Materials for High­ Temperature Thermoelectric Generators, Journal of Power Sources 410­411 (2019) 143­151.

DOI: 10.1016/j.jpowsour.2018.10.076

[8] F. Lihl, H. Ebel, W. Baumgartner, X­Ray Studies on Vegards Law, Metallkunde 62 (1970) 42­45.

[9] M. Liu, L. G. Liu, Compressions and Phase Transitions of Tin of Half a Megabar, High Temperature-High Pressure 18 (1986) 79­85.

[10] W. Parrish, Results of the IUCr Precision Lattice­Parameter Project, Acta Crystallographica 13 (1960) 838­850.

[11] S. Asbrink, A. Waskowska, CuO: X­ray Single­Crystal Structure Determination at 196 K and Room Temperature, Journal of Physics: Condensed Matter 3 (1991) 8173.

DOI: 10.1088/0953-8984/3/42/012

[12] J. Mao, Y. Wang, H. Kim, Z. Liu, U. Saparamadu, F. Tian, K. Dahal, J. Sun, S. Chen, W. Liu, Z. Ren, High Thermoelectric Power Factor in Cu-Ni Alloy Originate from Potential Barrier Scat­ tering of Twin Boundaries, Nano Energy 17 (2015) 279­289.

DOI: 10.1016/j.nanoen.2015.09.003