THE EROSION BEHAVIOR OF STEEL AS A FUNCTION OF MICROSTRUCTURE ON SOLID PARTICLE EROSION

The effects of the microstructure of two ductile steels on their solid particle erosion were determined. The steels chosen allowed microstructural changes to be made without drastically changing their hardness, which is reported to be a direct function of erosion resistance. The steels used were plain carbon 1075 and 1020 in the coarse pearlite, fine pearlite, and spheroidized forms for the 1075 and in three spherodized conditions for the 1020 steel. Single particle and multiple particle erosion tests were conducted using 240 {micro}m diameter SiC particles, angles of impingement of 15°, 30°, and 90° and velocities of 30.5 mps (100fps) and 61 mps (200fps). Both surface and subsurface analyses were conducted using scanning electron microscopy. In the room temperature erosion tests, the spheroidized microstructure of the 1075 steel eroded less than either of the two pearlitic microstructures. It was found that the pearlitic steels exhibited cracking at the eroded surface as well as beneath it, causing greater material removal. The spheroidized structure showed no surface cracking; however, cracking did occur at a depth of approximately 20 {micro}m below the surface. The carbide particle spacing in the 1020 spheroidized steel also had a measureable effect on the erosion rate, The hardness of the various microstructures had an inverse relation to the erosion rate