[01] Ibrahim Karaca, Department of Physics, Faculty of Science, Niğde University, Niğde, Turkey. [02] Mehmet Ali Güzel, Graduate School of Arts and Sciences, Niğde University, Niğde, Turkey.

Recently the interest about Bi-2212 superconductor for high magnetic field use has been enhancing despite the fact that an increase of the critical current is still needed to boost its successful use in such applications. The sintering time effect is investigated with using the Vickers hardness number for the BSCCO samples. The results of the Vickers hardness number are used to describe the indentation size effect (ISE) according to Oliver-Phar model. The different theoretical models are examined with the results of the hardness. It is found that the modified PSR model is convenient to analyzing the results of the hardness. The true hardness is related with the long sintering time, according to modified PSR model. From the relationship between the true hardness and sintering time, one can be drawn that the increase with the hardness range of sintering time 15h to 85h is positively affected the true hardness. But the longer sintering time than the 85 h is damagingly affected on the true hardness. From this it can be concluded that the grain size may be decrease for the longer sintering time than the 85 h in the bulk BSCCO samples. This can be attractive for the obtaining high magnetic field with superconducting Bi-2212 wire.

Micro-hardness, ISE, Sintering Time Condition, Bi-2212

[01] M. Yılmazlar, O. Ozturk, O. Gorur, I. Belenli, C. Terzioglu, Supercond. Sci. Tech. 20, 365 (2007). [02] B.W. Mott, Microindentation Hardness Testing, Butterworths, London, 1956. [03] H. Bückle, in: J.H. Westbrook, H. Conrad (Eds.), The Science of Hardness Testing and its Research Applications, ASME, Metals Park, OH, 1973, p. 199. [04] P.M. Sargent, T.F. Page, Proc. Bri. Ceram. Soc. 26 (1978) 209. [05] S.J. Bull, T.F. Page, E.H. Yoffe, Phil. Mag. Lett. 59 (1989) 281. [06] P.N. Kotru, A.K. Razdan, B.M. Wanklyn, J. Mater. Sci. 24 (1989) 793. [07] J. Guille, M. Sieskind, J. Mater. Sci. 26 (1991) 899. [08] T.F. Page, W.C. Oliver, C.J. McHargue, J. Mater. Res. 7 (1992) 450. [09] H. Li, R.C. Bradt, J. Mater. Sci. 28 (1993) 917. [10] Gong, J. H., Wu, J. J. and Guan, Z. D., Examination of the indentation size effect in low-load Vickers hardness testing of ceramics. J. Eur. Ceram. Soc., 1999, 19, 2625–2631. [11] H. Li, Y.H. Han, R.C. Bradt, J. Mater. Sci. 29 (1994) 5641. [12] A. Jain, A.K. Razdan, P.N. Kotru, B.M. Wanklyn, J. Mater. Sci. 29 (1994) 3847. [13] Q. Ma, D.R. Clarke, J. Mater. Res. 10 (1995) 853. [14] J.C. Pethica, R. Hutchings, W.C. Oliver, Phil. Mag. A 48 (1983) 593. [15] M. Baykal and I. Karaca, e-Journal of New World Sciences Academy, Volume: 7, 1, Article Number: 3A00441- pp. 11, (2012). [16] Kölemen U, Uzun O, Yılmazlar M, Güçlün, Yanmaz E., J Alloys Compd, 2006, 415: 300-306. [17] W.N Wang, M.F Tai, H.C Ku, M.J Shieh, T.Y Lin, Y.F Wang, H.B Lu, P.C Yao, S.J Yang, S.E Hsu, Supercond. Sci. Technol., 2 (1989), pp. 55–58 [18] H. Li, R.C. Bradt, J. Mater. Sci. 31 (1996) 1065. [19] K. Sangwal, Materials Chemistry and Physics 63 (2000) 145–152. [20] K. Sangwal, A.R. Patel, J. Phys. D.: Appl. Phys. 7 (1974) 2031. [21] H. Bückle, in: J.H. Westbrook, H. Conrad (Eds.), The Science of Hardness Testing and its Research Applications, ASME, Metals Park, OH, 1973, p. 199. [22] T.F. Page, W.C. Oliver, C.J. McHargue, J. Mater. Res. 7 (1992) 450. [23] H. Li, Y.H. Han, R.C. Bradt, J. Mater. Sci. 29 (1994) 5641. [24] Q. Ma, D.R. Clarke, J. Mater. Res. 10 (1995) 853. [25] S.M. Khalil, Journal of Physics and Chemistry of Solids 62, (2001), 457-466. [26] Bull, S. J., Page, T. F. and Yoffe, E. H., Phil. Mag. Lett., 1989, 59, 281–288. [27] Tabor, D., The Hardness of Metals. Oxford University Press, Oxford, UK, 1951. [28] H. Bückle, in: J.H. Westbrook, H. Conrad (Eds.), The Science of Hardness Testing and its Research Applications, ASME, Metals Park, OH, 1973, p. 199. [29] Sahin, O., Uzun, O., Kolemen U., and Uçar, N., J. Phys. Condens. Matter 19, (2007) 306001. [30] Gong, J., Wu, J., ve Guan, Z., Journal of European Ceramic Society, 19 (15), 2625-2631, (1999). [31] Kölemen, U., J. Alloys and Compd., 425 429-435, (2006). [32] Seki, H., Wongsatanawarid, A., Physica C, 470, 1177–1180, (2010). [33] Peng, Z., Gong, J. and Miao, H., Journal of the European Ceramic Society, 2004. [34] Weiss, H.J., Physica Status Solidi (a), 1987. [35] Çelebi, S., Kölemen, U., Malik, A. I. and Öztürk, A., Physica Status Solidi A, 194, 260-270, 2002. [36] I. Karaca, O. Uzun, U. Kölemen, F. Yılmaz, O. Şahin, J.Alloys And Compounds, 486-491, 2009. [37] Uzun, O., Kölemen, U., Çelebi, S. And Güçlü, N., J. Eur. Ceram. Soc., 25, 969-977, 2005. [38] Hays, C. and Kendall, E. G., Metall., 6, (1973) 275–282. [39] E.O. Bernhardt, Z. Metallkde 33 (1945) 135. [40] F. Fröhlich, P. Grau, W. Grellmann, Phys. Stat. Sol. (a) 42 (1977) 79. [41] B.-D. Michels, G.H. Frischat, J. Mater. Sci. 17 (1982) 329. [42] W.C. Oliver, R. Hutchings, J.B. Pethica, in: P.J. Blau, B.R. Lawn (Eds.), ASTM, Philadelphia, PA, 1986, p. 90. [43] Q. Ma, D.R. Clarke, J. Mater. Res. 10 (1995) 853. [44] G.P. Upit, S.A. Varchenya, Phys. Stat. Sol. 17 (1966) 831. [45] G.P. Upit, S.A. Varchenya, in: J.H. Westbrook, H. Conrad (Eds.), ASME, Metals Park, OH, 1973, p. 135. [46] I.G. Berzina, I.B. Berman, P.A. Savintsev, Kristallografiya 9 (1965) 483. [47] P.N. Kotru, A.K. Razdan, B.M. Wanklyn, J. Mater. Sci. 24 (1989) 793. [48] J.H. Westbrook, in: A.R.C. Westwood, N.S. Stoloff (Eds.), Environment-Sensitive Mechanical Behaviour, Gordon-Breach, New York, 1967, p. 247. [49] R.E. Hanneman, J.W. Westbrook, Phil. Mag. 18 (1968) 73. [50] J. Gil Sevillano, in: H. Mughrabi (Ed.), Plastic Deformation and Fracture of Materials, Ch. 2, VCH, Weinheim, 1993. [51] M.V. Swain, B.R. Lawn, Phys. Stat. Solidi 35 (1969) 909. [52] Hans Conrad and J. Narayan, Applied Physics Letters Volume 81, Number 12 16 September 2002. [53] J.H. Gong, J.J. Wu and Z.D. Guan, Mater. Lett. 35, (1998) 58. [54] W. Wang, G. Yamamoto, K. Shirasu, Y. Nozaka, T. Hashid, Journal of the European Ceramic Society, Volume 35, Issue 14, Pages 3903–3908 November 2015. [55] N. Redjdal, H. Salah, T. Hauet, H. Menari, S.M. Chérif, N. Gabouze, M. Azzaze, Thin Solid Films, Volume 552, 3 Pages 164–169, February 2014. [56] D. Wang, H. Zhang, X. Zhang, S. Tang, Y. Ma, H. Oguro, S. Awaji, K. Watanabe, Physica C: Superconductivity and its Applications, Volume 508, Pages 49–5515, January 2015.