Crack Orientation Dependence of Fatigue Behavior in Titanium Single Crystals by Thin Sheet Plain Bending


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Fatigue test of titanium single crystals with different crystallographic orientations has been carried. To investigate fatigue fracture behavior of small single crystals, plain bending fatigue test method for thin sheet specimen was developed. One end of the sheet specimen is fixed at a voice coil of the loudspeaker and the other end is set free. A bending mode resonance occurs in the specimen due to forced vibration at the fixed end. In A-specimen, a notch plane and the direction are (11 20) and [1100], respectively, the crack propagates parallel to {1100} plane and striation-like markings are observed on the fatigue surfaces. In B-specimen with a notch of (1100) [1120], the crack also propagates parallel to {1100} plane as similar to A-specimen. These cracks are deduced to extend by alternating shear on two intersecting prismatic slip systems at the crack tip. In F-specimen with a notch of (0001) [11 20], the crack propagates parallel to (0001) and some trace of pyramidal slip was observed on the fatigue surface. As a result, S-N curves of each specimen showed strong orientation dependence. Fatigue strength of F-specimen is higher than that of A- and B-specimen.



Key Engineering Materials (Volumes 326-328)

Edited by:

Soon-Bok Lee and Yun-Jae Kim




S. Ando et al., "Crack Orientation Dependence of Fatigue Behavior in Titanium Single Crystals by Thin Sheet Plain Bending", Key Engineering Materials, Vols. 326-328, pp. 967-970, 2006

Online since:

December 2006




[1] C. Laird and G. C. Smith : Philos. Mag., Vol. 7(1962), p.847.

[2] C. M. Ward-Close and C. J. Beevers : Metall. Trans. A, Vol. 11A(1980), p.1007.

[3] Y. Mine, S. Ando, K. Takashima, H. Tonda and Y. Higo : J. Jpn. Inst. Metals, Vol. 61(1997), p.41.

[4] Y. Mine, T. Yamada, S. Ando, K. Takashima, H. Tonda, Y. Higo and P. Bowen : Key Eng. Mater., Vols. 145-149(1998), p.721.


[5] S. Ando, Y. Mine, H. Tonda and K. Takashima : Ti-2003 Science and Technology, edited by G. Lütjering and J. Albrecht, WULEY- VCH (2004), p. (1933).

[6] P. G. Partridge : Metall. Rev., Vol. 12 (1967), p.169.

[1120] 500µm.

[1] G Fig. 8 Fatigue crack profile of the F-specimen at σa = 375MPa. Crack growth direction 10µµµµm.

[1120] .

[1100] .

[1120] .

[2110] G Fig. 9 Scanning electron micrograph of fatigue surface of F-specimen.