Abstract
We study the dislocation structure of a Tindash;5percnt;Alndash;5percnt;V alloy upon cyclic-strength and crack-propagation resistance tests with symmetrical tensionndash;compression loading with frequencies of 100 Hz, 500 Hz, 3 kHz, and 10 kHz. The identity of the test conditions has allowed us to carry out a comparative analysis of the influence of the loading frequency on the evolution of the dislocation structure in the material main volume during the fatigue-damage accumulation and in the fracture zone during the fatigue-crack propagation. It is shown that at these two loading stages the plastic-deformation micromechanisms adapt themselves to the loading rate. In the first case, this is due to the fact that a decrease in the activity of the work of the Frankndash;Read sources in high-frequency loading is compensated for by a more pronounced deformation of the alpha;-phase as a result of the formation of stacking faults. In the second case, the high level of local stresses activates the cross sliding and the formation of a honeycomb structure in the alpha;- and beta;-phases, and the elements of this structure decrease in size with increasing loading frequency. The incompleteness of relaxation processes in high-frequency cyclic loading is offset by the deformation of boundary volumes which are initially present in the alpha;-phase of twins.
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References
L. E. Matokhnyuk, Accelerated Fatigue Tests with High-Frequency Loading [in Russian], Naukova Dumka, Kiev (1988).
K. J. Miller and R. Akid, “The application of microstructural fracture mechanics to various metal surface states,” Proc. Roy. Soc. London. A, 452, No. 1949, 1411- 1432 (1996).
K. J. Miller, “A historical perspective of the important parameters of metal fatigue and problems for the next century,” in: Fatigue'99 (Proc. 7th Int. Congress, Beijing, China, 8- 12 June, 1999.), Vol. 1, High Education Press, Beijing (1999), pp. 15- 39.
Titanium Alloys. Metallography of Titanium Alloys [in Russian], Metallurgiya, Moscow (1980).
L. E. Matokhnyuk, G. N. Nadezhdin, and T. Yu. Yakovleva, “A study of fatigue fracture of titanium alloys over a wide range of loading frequencies,” in: Mechanical Fatigue of Metals (Proc. VIth Inter. Colloq.) [in Russian], Naukova Dumka, Kiev (1980).
B. A. Kolachev, Physical Metallurgy of Titanium [in Russian], Metallurgiya, Moscow (1976).
V. M. Kosevich and L. S. Palatnik (Eds.), Electron-Microscopic Images of Dislocations and Stacking Faults. A Handbook [in Russian], Nauka, Moscow (1976).
H. C. Gu, “Cyclic deformation and substructure evolution in titanium and zirconium,” in: Fatigue'99 (Proc. 7th Int. Congress, Beijing, China, 8- 12 June, 1999), Vol. 1, High Education Press, Beijing (1999), pp. 131- 138.
A. Suhua, W. Rhongguang, and X. Yuebo, “The fatigue deformation and fracture characteristics of coarse grained polycrystalline α-titanium,” Scr. Met., 19, No. 9, 1099- 1103 (1985).
J. Friedel, Dislocations, Pergamon Press, Oxford- London- Edinburg- New York- Paris- Frankfurt (1964).
M. L. Bernshtein and V. A. Zaimovskii, Structure and Mechanical Properties of Metals [in Russian], Metallurgiya, Moscow (1970).
N. Tanaka and H. Conrad, “Dislocation velocity in alpha-titanium,” Acta Met., 19, No. 10, 1001- 1008 (1971).
M. A. Krishtal and S. A. Golovin, Internal Friction and Structure of Metals [in Russian], Metallurgiya, Moscow (1976).
I. I. Novikov (Ed.), Advances in the Physics of Metals [in Russian], Metallurgizdat, Moscow (1956).
Science, Technology and Application of Titanium, Pergamon Press, Oxford- London (1970).
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Yakovleva, T.Y. Dislocation Structure of VT22 Titanium Alloy in Cyclic Loading with Various Loading Frequencies. Strength of Materials 32, 331–338 (2000). https://doi.org/10.1023/A:1026600617137
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DOI: https://doi.org/10.1023/A:1026600617137