Contact evolution based fretting fatigue prediction
Lead Research Organisation:
University of Oxford
Department Name: Engineering Science
Abstract
The design of complex couplings and connections against failure is a key topic for the optimisation of key aeroengine components, which represents a vital challenge for the sustained competitiveness of the British aeroengine industry. The difficulties associated with gaining access to the intimate contacting regions of such components provides an opportunity for computational modelling and predictive techniques. This project will bring about a quantum leap in the application of modelling techniques to the design of engineering contact connections through the consolidation of a number of different techniques. The key techniques that will be incorporated in the tool to be developed are: (i) finite element based modelling of material removal due to fretting wear action, (ii) asymptotic solutions for characterising the multiaxial stress states for cracking prediction at sharp contact edges and steep contact stress gradients, (iii) the use of multiaxial representative testing techniques for obtaining cycle-dependent frictional contact data(iv) a combined wear-fatigue prediction technique to provide a fretting fatigue damage parameter that captures the effects of slip amplitude.The tool will be applied to realistic three-dimensional aeroengine demonstrator components and validated against existing test data from previous EPSRC-funded work.
Publications
Cartwright R
(2011)
Long term wear of complete contacts subject to fretting
in Wear
Dini D
(2008)
An axi-symmetric Hertzian Contact subject to cyclic shear and severe wear
in Wear
Fleury R
(2017)
Incomplete contacts in partial slip subject to varying normal and shear loading, and their representation by asymptotes
in Journal of the Mechanics and Physics of Solids
Hills D
(2009)
What features are needed in a fretting fatigue test?
in Tribology International
Hills D
(2009)
Simulation of Fretting Wear in Halfplane Geometries: Part 1-The Solution for Long Term Wear
in Journal of Tribology
Hills D
(2015)
A discussion of "Numerical and experimental investigations on fretting fatigue: Relative slip, crack path, and fatigue life" by N. Noraphaiphipaksa, C. Kanchanomai, and Y. Mutoh
in Engineering Fracture Mechanics
Hills D
(2015)
Fretting in complete contacts - the use of Williams' solution
in Frattura ed Integrità Strutturale
Hills D
(2010)
The effect of wear on nucleation of cracks at the edge of an almost complete contact
in Wear
Nowell D
(2010)
Simulation of Fretting Wear in Half-Plane Geometries-Part II: Analysis of the Transient Wear Problem Using Quadratic Programming
in Journal of Tribology
Paynter R
(2007)
The effect of path cut on Somigliana ring dislocation elastic fields
in International Journal of Solids and Structures
| Description | The balance between fretting accelerated crack nucleation and wear damage was investigated. Emphasis was placed on the analysis of fretting wear using Archard wear law, employing calibrations for wear coefficients from sliding tests. In addition new results were found for the long-term solution for the fully worn contacts, and these are important because they are independent of the wear law employed. They enable the final state of the contact to be found without a detailed knowledge of the wear law. |
| Exploitation Route | The results are of direct applicability in any engineering design containing contacts where frettting is a known issue. They can be used at two levels; (a) if the wear law is known or can be found, from sliding tests then the precise evolution of the contact and its rate of change may be predicted; (b) if this information is not known we can still predict the final contact configuration, but we will not know how long it took to achieve that state. The most important outcome is the way that the steady state performance of all kinds of contacts can be predicted, without knowing the precise way in which the wear proceeds. We can therefore know the final worn configuration and see whether that is susceptible to nucleating cracks. This is of direct practical relevance in the design of all contact asssemblies where fretting and crack nucleation are potentially threats to the safety of a device, and can be applied directly to, for example, understanding and quantifying the strength of spline couplings in gas turbines. |
| Sectors | Transport |
| URL | http://www.eng.ox.ac.uk/solidmech/people/professor-david-hills/ |
| Description | Rolls-Royce plc make use of the fretting fatigue and wear analysis procedures developed. |
| First Year Of Impact | 2013 |
| Sector | Aerospace, Defence and Marine |
| Impact Types | Economic |
| Description | Rolls-Royce plc |
| Organisation | Rolls Royce Group Plc |
| Country | United Kingdom |
| Sector | Private |
| Start Year | 2007 |