Effects of inert gases on fatigue crack growth and their transportation into subsurface regions in titanium

Abstract

To clarify the effects of inert gases on the fatigue behavior of titanium, fatigue crack growth tests were carried out in pure inert gases and in vacuum. Fatigue crack growth rates increased, and the fracture surface appearance was changed in inert gases, as compared to those in vacuum. The transportation of inert gases into subsurface regions of fracture surfaces was confirmed using Auger electron spectroscopy. This transportation is considered to be due to the reverse slip of slip planes on which inert gas atoms have adsorbed.

Fatigue Damage Mechanism of Titanium in Inert Environments

“…Fatigue properties in metal are strongly dependent on testing atmospheres, e.g. fatigue damaged surfaces exhibit different features of microstructures in air from those in vacuum [1][2][3][4][5][6][7][8]. Numerous studies have been published on metals and alloys possessing a face-centered cubic (fcc) and bodycentered cubic (bcc) structures.…”

A quantitatively accurate theory of stable crack growth in single phase ductile metal alloys under the influence of cyclic loading

“…Explanations that have been offered in the past have included the idea that a crack can not grow distances of less than one or two atoms, crack closure in terms of both surfaces, plasticity, and oxide formation, and a variety of other possible explanations for such behavior. Suresh et al (1981); Steinbock and gudladt (2011); Petit and Sarrazin-Baudoux (2006); Kobayashi et al (1997); Gall and et al (2005); Henaff et al (1995); Ismarrubie and Sugano (2004); Kelestemur and Chaki (2001); Shimojo et al (2000); Kelestemur and Chaki (2001); Yakushiji et al (2001) The idea that a crack can't grow less than one atom fails when the crack is considered in three dimensions. If only half of a crack front advances one atomic diameter, the overall growth of the crack could be considered to be 0.5 atomic diameters.…”