Tenue à l’usure d’un acier ordinaire à dépôt d’alumine par plasma

Abstract

The work undertaken in this memory consists in studying mainly the behavior with wear of two steels ordinary, one covered by plasma of a layer of alumina and the other of a composite layer titanium alumina and oxide. This study was accompanied by a comparative study with an aluminium alloy also covered with a layer of austenitic steel by deposition plasma. After characterization of the substrate, where it was shown that this material has a good ductility of the heart, his behavior with wear is very poor. The improvement made by the deposition plasma relates to the increase in hardness initially. The layers of alumina or it composite ceramics do not have a good behavior with wear under the conditions present of deposition or tests. Their coefficient of wear is very close to that of the substrate. The detachment of the remains was carried out by crumbling of the layer. In addition, the improvement of the properties of aluminium alloy surface by the deposition plasma was clearly proven. Indeed, the layer of steel led to an increase in hardness, and a significant reduction of wear. It was shown that wear soft and is controlled by a mechanism of abrasion. The profile of hardness in bottom of the tracks highlighted a hardening by work hardening due to the cyclic passage of the pawn on the layer.