Pushout and push-back tests are performed on monofilament modelcomposites SiC/Pyrex, by using an indentation apparatus where thestiffness of the loading device can be changed. Under low stiffness,the sliding exhibits stick-slip motion and steady slip under highstiffness. Duromg push-out/push-back cycling, the applied loaddecreases slowly indicating interfaceal wear and progressivereduction of the effective interfacial shear stress. The radialclamping stress on the fibre is due to a combined effect of thethermal misfit and of an additional dilatancy coming from thecrushing of the asperities. By Fush-hack, the load-displacement curveexhibits a seating drop when the fihre reaches its onginal positionagain. Analysis of steady and serrated motion shows that the maininterfacial wear occurs under low velocity sliding. Sliding velocityjumps indicate that the local contacts failures are creep controlled.All these features are described and discussed with regards to thephysics of' dry friction and micromechanics..
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