Fretting Fatigue Properties of Two Near-.ALPHA. Titanium Alloys.

In order to investigate the basic fretting fatigue properties of two kinds of near-α titanium alloy, fretting fatigue tests were carried out under axial loading conditions using a bridge-type contact plece. The influence of contact pressure on fretting fatigue properties was also investigated. The main results obtained are as follows. In both materials, fretting reduced the fatigue lives by a factor of four as a result of the initiation of the fatigue crack at early stage of life and acceleration of the crack propagation rate. Fretting fatigue lives decreased with increasing contact pressure. The difference in fretting fatigue lives among the materials used is explained by different of tangential force coefficients and fatigue crack growth properties, as well as compressive residual stress introduced by shot peening.