Fretting‐fatigue analysis of shot‐peened aluminium and titanium test specimens

Abstract

In the last decades, many alleviation measures were proposed in order to improve the life of fretting fatigue‐affected components. In such a context, the shot peening treatment is worth noting. Therefore, in the present paper, the fatigue life of shot‐peened aluminium and titanium alloy specimens, subject to fretting fatigue under partial slip regime, is assessed by means of the Carpinteri et al. criterion for fretting fatigue. First, according to the superposition principle, the relaxed residual stresses (due to the shot peening treatment) are combined with the stress components due to fretting fatigue loading. Then fretting fatigue assessment is performed. In such a context, a novel theoretical law for the relaxed residual stress field is here proposed, the implementation of which shows very promising results in terms of fretting fatigue life estimation of the shot‐peened specimens examined.

Residual Stress Distribution Design for Gear Surfaces Based on Genetic Algorithm Optimization

“…where x = (σ surface , σ max , y max , y core ) is called an individual in GA. Each component of the individual is called a "gene". The constraints in Equation (8b-g) are summarized from the existing experimental [38][39][40][41] and theoretical [13,42] results for RS distribution profiles produced using the shot peening process.…”

Structural integrity of shot peened Ti6Al4V specimens under fretting fatigue

“…A theoretical law to evaluate the relaxed residual stress profile in the above situation has been recently proposed by some of the present authors (Vantadori and Zanichelli 2020). More precisely, the self-equilibrated stress profile, formulated by observing the experimental evidence (Araújo and Nowell 2009;Farrahi et al 1995;Gao et al 2002;Higounenc 2005;Sabelkin et al 2005;Kirk 2014), is idealised as follows:…”

“…Note that residual stresses are constant and, therefore, affect the fatigue behaviour of the material in the same way as a static loading or the mean value of a cyclic loading applied to the specimen. The theoretical law proposed in Vantadori and Zanichelli (2020) is useful particularly when no details concerning the actual residual stress depth profiles are available, as occurs in the present case.…”

“…Therefore, in the present paper, an experimental testing on the standard configuration (a cylinder against a flat specimen) (Araújo and Nowell 2009) is examined and simulated by applying the Carpinteri et al criterion for fretting fatigue (Carpinteri et al 2019;Vantadori et al 2019Vantadori et al , 2020aVantadori and Zanichelli 2020;Zanichelli and Vantadori 2020). The specimens, provided by Rolls-Royce, were made by Ti6Al4V and shot peened according to Rolls-Royce specifications (Araújo and Nowell 2009).…”

Influence of normal load frequency on fretting fatigue behaviour by a critical plane-based approach

“…In the present paper, the experimental tests carried out by Majzoobi and Abbasi [25] on an Al 7075-T6 aluminium alloy are simulated by employing a critical plane-based multiaxial criterion formulated for fretting fatigue [52][53][54]. Such a criterion was previously applied to different fretting fatigue problems, on either cylindrical-or spherical-toflat contact configurations, with a constant normal load applied to the pads.…”