A novel formulation for radial fretting wear: Application to false brinelling in thrust bearings
Cubillas D., Olave M., Llavori I., Ulacia I., Larrañaga J., Zurutuza A., Lopez A.
Radial fretting is defined as the damage caused by the relative motion of a ball under a variable normal load. The conducted experimental tests proved the existence of this damage even in contacting bodies with similar materials and elastic properties; however, the reviewed analytical methods do not predict damage under these conditions, and the numerical methods are time-consuming, especially when the investigation requires the analysis of several loading cases or during large number of cycles. The main objective of this work was to develop a fast analytical method to analyse radial fretting wear. For this purpose, a novel formulation for contact displacements under a normal variable load was built and merged to different contact mechanic formulas. For validation purposes, false brinelling in thrust bearings was used as a representative industrial example. The results were compared with a FEM model showing a relative difference under 9% and a massive reduction of the calculation time of more than 30 000 times, moreover experimental tests were carried out, showing a good agreement between the density of friction energy and the obtained fretting damage what endorse the use of this formulation for the analysis of a large number of cycles and loading cases.