Effect of Solid Particle Erosion on the Aqueous Corrosion Behaviour of a Ti6Al4V Sheet

Abstract

The economic and effective operation of machinery and plant involved in fluids handling is increasingly dependent on the utilization of materials that combine high corrosion resistance and good wear resistance.The present study was undertaken in order to investigate the effect of solid particle erosion on the surface characteristics, the microstructure and the aqueous corrosion behavior of a Ti6Al4V sheet metal alloy. The scope of the present effort is to examine the possible way the solid particle erosion affect, by altering the Ti6Al4V surface characteristics, the subsequent electrochemical corrosion response. As for the solid particle erosion tests, three (3) different impact angles were selected, 30°, 60° and 90° degrees respectively. Angular alumina particles of 177 -250 μm size was used as the eroding media, injected, under 1 and 2 bars pressure, on the sample surface located at 10 mm distance from the injection nozzle. The mass loss was weighted and the wear rates were calculated. Surface roughness of the eroded surfaces was assessed and the microstructural modifications were evaluated using optical microscopy and SEM-EDX.Cyclic polarization measurements were conducted in an electrolyte simulating body fluids in order to ascertain the corrosion response of the surface treated samples. SEM-EDX analysis of the corroded surfaces was used in order to assess the corrosion mechanisms and the involved phenomena and to correlate them with the surface and the overall microstructural modifications.