Casting Simulations of Arsenical Copper: New Insights into Prehistoric Metal Production and Materials

Abstract

To improve our understanding of prehistoric casting methods and materials, simulations for copper arsenic (As-Cu) alloys with up to 15 wt.% As were calculated. Cooling curves and the secondary dendritic arm spacings (SDAS) for the alloy were plotted and calculated, respectively, under non-steady-state conditions with a time-stepping procedure for prehistoric mold materials (e.g., quartz sand, sandstone, terracotta, and steatite). The cooling and microstructure of the alloy was also simulated in iron molds for immediate comparison with as-cast microstructure. The microstructure and SDAS of the as-cast alloys were studied and measured in polished samples with a metallographic microscope. The purpose of this research was to improve our ability to retroactively evaluate the influence of mold materials on as-cast microstructures and determine their materials. This article focuses on As-Cu alloy microstructure and SDAS values, and also discusses the phenomenon of “inverse segregation” and its relation to cooling rate and As concentration.

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(adapted from23).

Abbreviations

A :

Mold metal interface (m2)

α :

Overall heat transmission coefficient (W m−2 K−1)

c :

Specific heat of the mold (J kg−1 K−1)

c m :

Specific heat of the metal (J kg−1 K−1)

c 0 :

Alloy concentration (wt.%)

c l :

Concentration of the liquid phase (wt.%)

D :

Diffusion coefficient (m2 s−1)

h :

Heat transfer coefficient (W m−2 K−1)

k :

Thermal conductivity of the mold (W m−1 K−1)

k 0 :

Partition coefficient

f s :

Mass fraction of solid phase

m :

Slope of the liquidus line (K wt.%−1)

n :

Time-step sequence (10−3 s)

t :

Time (s)

t f :

Local solidification time (s)

T :

Temperature of the metal (K)

T 0 :

Ambient temperature of the mold (K)

v :

Volume of casting (m3)

ΔT :

Solidification interval (K)

ΔHf :

Latent heat of fusion (J mol−1)

ρ :

Density of the mold (kg m−3)

ρ m :

Density of the metal (kg m−3)

Γ :

Gibbs–Thomson coefficient (K m)

λ :

Secondary dendritic arm spacing (µm)

References

  1. 1.

    M. Mödlinger and B. Sabatini, J. Archaeol. Sci. 74, 60 (2016). https://doi.org/10.1016/j.jas.2016.08.005.

    Article  Google Scholar 

  2. 2.

    M. Mödlinger, D. Macció, A. Cziegler, H. Schnideritsch, and B. Sabatini, Metall. Mater. Trans. B 49, 2505 (2018). https://doi.org/10.1007/s11663-018-1322-8.

    Article  Google Scholar 

  3. 3.

    H. Lechtman, J. Field Archaeol. 23, 477 (1996). https://doi.org/10.2307/530550.

    Article  Google Scholar 

  4. 4.

    H. Lechtman and S. Klein, J. Archaeol. Sci. 26, 497 (1999).

    Article  Google Scholar 

  5. 5.

    T. Rehren, L. Boscher, and E. Pernicka, J. Archaeol. Sci. 39, 1717 (2012).

    Article  Google Scholar 

  6. 6.

    E.C. Rollason, Metallurgy for Engineers (London: Edward Arnold & Co, 1949).

    Google Scholar 

  7. 7.

    E.G. Garrison, A History of Engineering and Technology. Artful Methods, 2nd ed. (Boca Raton: CRC Press, 1998).

    Google Scholar 

  8. 8.

    J. Günter, K.J.A. Kundig, and J.A. Konrad, Copper: Its Trade, Manufacture, Use, and Environmental Status (Materials Park: International Copper Association, 1999).

    Google Scholar 

  9. 9.

    A. Nayar, The Metals Databook (New York: McGraw-Hill Companies, 1997).

    Google Scholar 

  10. 10.

    A. Giumla-Mair, Surf. Eng. 24, 110 (2008).

    Article  Google Scholar 

  11. 11.

    F. Pereira, R.J.C. Silva, A. Soares, M. Araújo, and J. Cardoso, Mater. Manuf. Process. 21, 1 (2016).

    Google Scholar 

  12. 12.

    H. Lechtman, Hist. Metall. 19, 141 (1985).

    Google Scholar 

  13. 13.

    P.D. Budd, A Metallographic Investigation of Eneolithic Arsenical Copper (Bradford: University of Bradford, 1991).

    Google Scholar 

  14. 14.

    P.D. Budd, Hist. Metall. 25, 99 (1991).

    Google Scholar 

  15. 15.

    P.J. Northover, Old Work Archaeometallurgy, ed. A. Hauptmann, E. Pernicka, and G.A. Wagner (Bochum: Deutsches Bergbau-Museum, 1989), pp. 111–118.

    Google Scholar 

  16. 16.

    J.R. Marechal, Métaux Corros. Ind. 33, 377 (1958).

    Google Scholar 

  17. 17.

    B.R. Subramanian and D.E. Laughlin, Bull. Alloy Phase Diagr. 9, 605 (1988).

    Article  Google Scholar 

  18. 18.

    B. Pei, B. Björkman, B. Jansson, and B. Sundman, Z. Metall. 85, 178 (1994).

    Google Scholar 

  19. 19.

    D.M. Stefanescu, Science and Engineering of Casting Solidification (New York: Springer, 2015).

    Google Scholar 

  20. 20.

    R.N. Grugel, J. Mater. Sci. 8, 677 (1993). https://doi.org/10.1007/BF01151244.

    Article  Google Scholar 

  21. 21.

    N.V. Ryndina and L.V. Kon‘kova, Sov. Archeol. 2, 30 (1982).

    Google Scholar 

  22. 22.

    ASM Handbook: Properties and Selection: Nonferrous Alloys and Special-Purpose Materials (ASM Handbook) Vol. 2.

  23. 23.

    E. Jochum-Zimmermann, N. Künzler-Wagner, and U. Kunnert, Exp. Archäol. Eur. 1, 285 (2005).

    Google Scholar 

  24. 24.

    W. Kurz and D.J. Fisher, Fundamentals of Solidification (Baech: Trans Tech Publications, 1986).

    Google Scholar 

  25. 25.

    A. Cziegler, Aspects of Grain Refinement in Copper Alloys, Master Thesis, Montanuniversität Leoben, 2015.

  26. 26.

    T. Ejima and M. Kameda, J. Jpn. Inst. Met. Mater. 1, 96 (1969).

    Article  Google Scholar 

  27. 27.

    M. Mödlinger and B. Sabatini, J. Archaeol. Sci. Rep. 16, 248 (2017). https://doi.org/10.1016/j.jasrep.2017.10.018.

    Article  Google Scholar 

  28. 28.

    M. Easton, C. Davidson, and D. St. John, Metall. Mater. Trans. A 41, 1528 (2010). https://doi.org/10.1007/s11661-010-0183-9.

    Article  Google Scholar 

  29. 29.

    M.B. Djurdjevic and M.A. Grzincic, Arch. Foundry Eng. 12, 19 (2012).

    Article  Google Scholar 

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Acknowledgements

Dr. Benjamin J. Sabatini is an International Research Fellow of the Japan Society for the Promotion of Science (JSPS) No. PE17781. This work was also supported by the European Union’s Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Actions Grant No. 656244.

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Sabatini, B.J., Cziegler, A. & Mödlinger, M. Casting Simulations of Arsenical Copper: New Insights into Prehistoric Metal Production and Materials. JOM 72, 3269–3278 (2020). https://doi.org/10.1007/s11837-020-04210-8

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