Correlation of fretting fatigue experimental results using an asymptotic approach

Fretting in complete contacts - the use of Williams’ solution

“…At the outset, a distinction should be made between incomplete contacts and complete contacts. For the former of these, the relevant asymptotic forms take a particular form (square-root bounded), and the tremendous amount of data generated in many laboratories throughout the world has been very satisfactorily correlated [13]. In contrast, complete contacts are much more challenging to characterise, and an important starting point is to think of them not as contacts between two components brought together, but as a monolithic entity which may be split, even separated, along small parts of the contact, especially the edges.…”

Fretting fatigue tests on shrink-fit specimens and investigations into the strength enhancement induced by deep rolling

“…The flat and rounded contact problem can be viewed as the merging of the ''inner" and the ''outer" (or Hertzian) asymptotes, which define the pressure and the friction traction distributions at the edge of the contact [34,35,40,42,[65][66][67]. Fig.…”

“…The modelling approaches to fretting fatigue are summarised by Nowell et al [34], Hills et al [35] and are: analogies either with crack or notch, Ciavarella [36][37][38] and Naboulsi [39]; asymptotic approaches both for complete and incomplete contacts, Dini, Nowell, Hills et al [34,35,[40][41][42][43]; short crack arrest on the KitagawaTakahashi (KT) diagram, Araújo et al [19,20,44] and Vallelano et al [45]; and finally a multiaxial fatigue critical plane approach, usually associated with a material size in order to incorporate the gradient effect, Araújo et al [19,20,46]. Of these approaches, crack arrest implicitly assumes that fretting is a tensile driven fatigue mechanism, indeed the reference threshold Stress Intensity Factor (SIF) is according to the mode I, which is the opening mode.…”

Partial slip incomplete contacts under constant normal load and subject to periodic loading

“…The method is very simple to apply, but the price one pays for the simplicity is that it may only be used when the slip region is a relatively small fraction of the contact half-width; that is, it will not work when the problem approaches the sliding condition. On the other hand, that does not often arise in practice, and the major advantage is that we may infer material properties from a simple laboratory test [10] which are transferable between a wide range of prototypical geometries.…”