COMPARISON OF WEAR BEHAVIOR OF PLASMA-SPRAYED AL2O3 COATINGS WITH ANDWITHOUT LASER TREATMENT

This paper studies experimentally the effects of CO2 laser-treatment o n the wear behaviour of plasma-sprayed Al2O3 coatings, in linear conta ct sliding (dry, abrasive and lubricated) against SAE 4620 steel. Test s were carried out using a block-on-ring friction and wear tester, und er different loads at different speeds. The wear mechanism and the cha nges in adherence, porosity and microstructure by laser treatment were also investigated. Results show a better wear behaviour for both lase r-treated ceramic coating and its paired steel under dry and abrasive conditions, compared with the case without laser treatment. The lubric ated wear behaviour of the laser-treated ceramic coating, however, is not improved. The changes in microhardness, porosity and adherence cau sed by the laser treatment are responsible for the change in wear beha viour of the ceramic coating. Copyright (C) 1996 Elsevier Science Ltd