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Microstructure and Thermal Stability of Ultra Fine Grained Mg and Mg-Gd Alloys Prepared by High-Pressure Torsion

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Abstract:

Bulk samples of pure Mg and Mg-Gd alloys were prepared by high-pressure torsion (HPT). The HPT made samples exhibit ultra fine grained (UFG) structure with grain size around 100 nm. Results of microstructure investigations of the UFG samples obtained by positron lifetime (PL) spectroscopy, transmission electron microscopy (TEM) and X-ray diffraction (XRD) are presented. In particular, lattice defects introduced by HPT were characterized. The data obtained at atomistic level are compared with macroscopic properties given by microhardness measurements.

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Periodical:

Materials Science Forum (Volume 482)

Pages:

183-186

DOI:

https://doi.org/10.4028/www.scientific.net/MSF.482.183

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Online since:

April 2005

Authors:

Jakub Čížek, Ivan Procházka, Bohumil Smola, Ivana Stulíková, Radomír Kužel, Z. Matěj, V. Cherkaska, Rinat K. Islamgaliev, Olya B. Kulyasova

Keywords:

Defect, Magnesium Alloy, Positron Annihilation, Severe Plastic Deformation (SPD)

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© 2005 Trans Tech Publications Ltd. All Rights Reserved

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References

[1] P. Vostrý, B. Smola, I. Stulíková, F. von Buch, B.L. Mordike: phys. stat. sol. (a) Vol. 175 (1999), p.491.

DOI: 10.1002/(sici)1521-396x(199910)175:2<491::aid-pssa491>3.0.co;2-f

Google Scholar

[2] R.Z. Valiev, R.K. Islamgaliev, I.V. Alexandrov: Prog. Mat. Sci. Vol 45 (2000), p.103.

Google Scholar

[3] F. Bečvář, J. Čížek, L. Lešťak, I. Novotný, I. Procházka, F. Šebesta, Nucl. Instr. Meth. A Vol. 443 (2000), p.557.

Google Scholar

[4] I. Procházka, I. Novotný, F. Bečvář, Mat. Sci. Forum Vol. 225-257 (1997), p.772.

Google Scholar

[5] M.J. Puska, R.N. Nieminen, J. Phys. F: Met. Phys. Vol. 13 (1983), p.333.

Google Scholar

[6] P. Hautojärvi, C. Corbel, in: Proceedings of the International School of Physics Enrico Fermi, Course CXXV, (Ed. A. Dupasquier, A.P. Mills), IOS Press, Varena 1995, p.491.

Google Scholar

[7] M. Fahnle, B. Meyer, J. Mayer, J.S. Oehrens, G. Bester, in: Diffusion Mechanisms in Crystalline Materials (Ed.: Y. Mishin et al. ) MRS Symposia Proceedings No. 527, p.23.

Google Scholar

[8] J. Čížek, I. Procházka, F. Bečvář, I. Stulíková, B. Smola, R. Kužel, V. Cherkaska, R.K. Islamgaliev, O. Kulyasova, to be submitted.

DOI: 10.4028/www.scientific.net/msf.482.183

Google Scholar

[9] J. Čížek, I. Procházka, G. Brauer, W. Anwand, R. Kužel, M. Cieslar, R.K. Islamgaliev, phys. stat. sol. (a) Vol. 195 (2003), p.335. r (mm).

DOI: 10.1002/pssa.200305929

Google Scholar

1 2 3 4 I2 (%).

Google Scholar

[60] [65] [70] [75] [80] [85] [90] [95] r (mm).

Google Scholar

1 2 3 4 5 Hv (MPa).

Google Scholar

500 1000 1500 2000 2500 3000 a) b) Fig. 2: Dependence of a) microhardness b) relative intensity of the PL defect component on the radial distance r from the center of sample. Full circles - HPT deformed Mg-10wt. %Gd, open circles - HPT deformed Mg.

Google Scholar