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Core Structure And Mobility Of a <101] Dislocations In L10 TiAl

Published online by Cambridge University Press:  22 February 2011

S. Rao ,
C. Woodward ,
J. Simmons  and
D. Dimiduk
S. Rao
Affiliation:
UES, Inc.; Dayton, OH 45432
C. Woodward
Affiliation:
UES, Inc.; Dayton, OH 45432
J. Simmons
Affiliation:
NRC Research Associate, WL/MLLM, WPAFB, OH 45433
D. Dimiduk
Affiliation:
WL/MLLM, Materials Directorate, Wright Laboratory, WPAFB, OH 45433
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Abstract

An empirical atomistic potential, fit to the structural and elastic properties of L10 TiAl within the embedded atom method (EAM), is used to simulate the mobility of two possible planar forms of a<101] dislocations in a model L10 compound. The two configurations examined were: the planar SISF-APB-CSF coupled (P core) and the decomposed 1/2<110]-SISF-SESF coupled (D core). Six different line orientations are considered for the P core: 0° (screw), 30°, 60°, 90° (edge), 120° and 150°. The ‘ideal’ friction stress at 0°K of a<101] dislocations in the P form is found to be a function of line orientation, with the close packed line directions, <101] (screw) and <110] (60°), having friction stresses ranging from 0.001–0.002μ. Previously calculated results on the friction stress of a/2<110] dislocations, using an identical potential are consistently higher than the friction stress of a<101] dislocations. Simulations of the interaction of glide strains with the D core for the 60° (line directions < 110]) and 120° (line directions <011]) orientations show that the Shockley partial trailing the SESF in the D core is strongly pinned. The dislocation moves by extension of SESF when glide stresses are applied with SESF as the trailing fault.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 364: Symposium L – High-Temperature Ordered Intermetallic Alloys–VI , 1994 , 129
Copyright
Copyright © Materials Research Society 1995

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References

1). Hug, G., Loiseau, A., and Lasalmonie, A., Phil.Mag. A54, 47(1986).Google Scholar
2). Hug, G., Loiseau, A., and Veyssiere, P., Phil.Mag. A57, 499(1988).Google Scholar
3). Sriram, S., PhD thesis, University of Cincinnati (1994); this conference proceedings.Google Scholar
4). Phan, I., PhD thesis, University of Paris (1993).Google Scholar
5). Kawabata, T., Kanai, T. and Izumi, O., Acta. Metall. 33, 1355(1985).Google Scholar
6). Kawabata, T., Abumiya, T., Kanai, T. and Izumi, O., Acta Metall. 38, 1381(1990).Google Scholar
7). Louchet, F. and Viguier, B., submitted to Phil. Mag. A, preprint ; this conference proceedings.Google Scholar
8). Inui, H., Private Communication ; M. Yamaguchi , this conference proceedings.Google Scholar
9). Sun, Y., this conference proceedings.Google Scholar
10). Stucke, M.A., Dimiduk, D. and Hazzledine, P., Proc. Symp on High Temperature ordered intermetallic alloys 5, Materials Research Society, 1993, p.471.Google Scholar
11). Stucke, M.A., Vasudevan, V. and Dimiduk, D., Mat. Sci. Eng., in press.Google Scholar
12). Dimiduk, D., Physique, J. de. III, Special issue Mechanisms of deformation and strength in Advanced Materials, Aussois, France(1990).Google Scholar
13). Grinberg, B.A., Antonova, O.V., Indenbaum, V.N., Karkina, L.E., Notkin, A.B. and Ponomarev, M.V., ‘Dislocations in TiAl - Part 1’, Institute of Metal Physics, Ural division of the USSR Academy of Science, 3(1989).Google Scholar
14). Grinberg, B.A., Phys. Stat. Sol. (b), 55, 59(1973)Google Scholar
15). Grinberg, B.A., Anisimov, V.I., Gornostirev, Y.N. and Taluts, G.G., Scripta Metall. 22, 859(1988).Google Scholar
16). Court, S.A., Vasudevan, V.K. and Fraser, H.L., Phil. Mag A, 61, 141(1990).Google Scholar
17). Simmons, J.P., Rao, S.I. and Dimiduk, D., Mat. Res. Soc. Symp. Proc. 288, 335(1993).Google Scholar
18). Woodward, C., Mclaren, J.M. and Rao, S., J. Mater Res. 7, 1735(1992).Google Scholar
19). Fu, C.L. and Yoo, M.H., Mat. Res. Soc. Symp. Proc. 186, 265(1990).Google Scholar
20). Freeman, A., private communication.Google Scholar
21). Tichy, G., Vitek, V. and Pope, D.P., Phi. Mag A, 53, 467(1986).Google Scholar
22). Simmons, J.P., Rao, S.I. and Dimiduk, D., in ‘Alloy Modelling and Design’, edited by Stocks, G.M. et al, TMS (1994).Google Scholar
23). Vitek, V. in ‘Dislocations and Properties of Real Materials’, Proc. of the conference to celebrate the 50th anniversary of the concept of dislocations in crystals, The Institute of Metals, London, 30(1985).Google Scholar
24). Voter, A. and Chen, S.P., Mat. Res. Soc. Symp. Proc. 82, 175(1990).Google Scholar
25). Rao, S., Woodward, C. and Parthasarathy, T.A., Mat. Res. Soc. Symp. Proc. 213, 125(1991).Google Scholar
26). Asta, M., DeFontaine, D. and Van Schilfgaarde, M., J. Mat. Res. 8, 2554(1993)Google Scholar
27). Freeman, A. et al., unpublished calculations.Google Scholar
28). Mehl, M.J., Osburn, J.E., Papaconstantopoulos, D.A. and Klein, B.M., Mat. Res. Soc. Symp. Proc. 186, 277(1990).Google Scholar
29). Pearson, W.B., ‘A Handbook of Lattice Spacings and Structure of Metals and Alloys - Vols 1 and 2’, Pergamon Press, Oxford(1987)Google Scholar
30). Hultgren, R., Orr, R.L., Anderson, P.D. and Kelly, K.K., ‘Selected Values of Thermodynamic Properties of Binary Alloys’, John Wiley and Sons Inc., New York(1963)Google Scholar
31). Rao, S., Woodward, C. and Parthasarathy, T.A., to be submitted to Phil. Mag A.Google Scholar
32). Simmons, J.P., Mills, M. and Rao, S., this conference proceedings.Google Scholar
33). Stroh, A.N., Phi. Mag. 3, 625(1958).Google Scholar
34). Vitek, V., Crystal Lattice Defects 5, 1(1974).Google Scholar