Impact of Atmospheric Plasma Spray Parameters on Cavitation Erosion Resistance of Al2O3-13% TiO2 Coatings |
| L.Łatka a, M. Szalab, M. Michalaka, T. Pałkac
aMechanical Department, Wrocław University of Science and Technology, Łukasiewicza St. 5, 50-371, Wrocław, Poland bLublin University of Technology, Faculty of Mechanical Engineering, Department of Materials Engineering, Nadbystrzycka St. 36, 20-618 Lublin, Poland cLublin University of Technology, Faculty of Mechanical Engineering, Production, Nadbystrzycka St. 36, 20-618 Lublin, Poland |
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| In this paper the results of cavitation erosion test of ceramic coatings are presented. The Al2O3-13% TiO2 coatings were manufactured by powder atmospheric plasma spraying. The plasma spray experimental parameters included two variables: (i) spray distance varying from 80 to 100 mm and (ii) torch linear speed varying from 300 to 500 mm/s.The as sprayed surface roughness was measured. The coatings structure was investigated using SEM. Porosity was investigated according to the ASTM E2109-01 Standard procedure. Additional microhardness measurements were conducted. The cavitation tests were carried out on vibratory test rig according to the ASTM G-32 standard regarding to the stainless steel (grade 304) reference sample. The cavitational worn areas were examined using SEM microscopy and roughness measurements. The influence of coatings microstructure and microhardness on the cavitation erosion resistance was investigated. The coatings microstructure was strongly dependent on spray distance as well as torch linear velocity. Decrease of the hardness was a result of less compact structure and lower degree of well molten particle. On the contrary, the best cavitation erosion resistance was characteristic for coatings which have quite good and compact structure but on the other hand the heat flux was lower. Higher heat flux caused thermal stresses, which were visible as cracks in the structure. Moreover, the type of the structure was important because from the point of view of the cavitation erosion resistance, lamellar architecture is more preferred than the columnar one. Finally, the structure type was linked to the process parameters. |
DOI:10.12693/APhysPolA.136.342 PACS numbers: 52.77.-j, 81.15.-z |