Degradation of ferritic X10CrAlSi18 stainless steel caused by slurry

Abstract

The slurry erosion tests of ferritic X10CrAlSi18 steel were carried out using a slurry pot device. In order to investigate the erosion process, two series of tests were performed: first one with a constant impact velocity of 5 m/s, 7 m/s and 9 m/s and the second one, during which the impact velocity was changed after every exposure. During each test, an influence of test conditions on volume loss, surface hardness and roughness with exposure time was studied. The normalized erosion rate and erosion efficiency parameter increased linearly with velocity in the range between 5 and 9 m/s. Surface hardness increased exponentially with an exponent n = 0.27. The erosive efficiency parameter determined for tests carried out with variable impact velocity was higher than for tests with constant velocity. The erosion performance increased as the difference in consecutive impact velocity increased. At the beginning of slurry tests, surface hardness and roughness increased rapidly. A fluctuation in erosion rate and surface roughness was noted in the tests performed with variable impact velocity. The amplitudes of these fluctuations decreased with the test duration. Surface hardness influenced damage formed on the specimen’s surface. With increasing surface hardness, surface roughness (Ra parameter) decreased. For surface hardness over 280 HV flakes were formed on the specimen surface.