Adhesive transfer in aero-engine abradable linings contact

Wear of abradable linings has been investigated on a scaled test rig platform, re-creating the wear mechanisms observed between the blade tip and abradable material that occur in an aero-engine compressor. The characterisation of the wear process has been performed using a stroboscopic imaging technique, capable of investigating the nature of the blade tip strike on the abradable, and the adhesive transfer of the material to the blade tip during a test. It was found in tests with low incursion rates that there was adhesive transfer, whereas with high incursion rates a cutting behaviour was observed. Analysis with the stroboscopic imaging technique allowed the adhesive transfer during the test as a function of the rub length to be recorded. Three phases were identified for adhesive transfer during test; an initiation phase with low rate of adhesion, steady state adhesion, and fracture of adhered material followed by re-initiation. These results also highlight how the standard practice of performing analysis of adhered material at the end of a test does not necessarily characterise the overall mechanics of adhesive transfer satisfactorily.