Experimental study to estimate the surface wear of nuclear graphite in HTR-PM

The aim of this study was to simulate the surface wear of graphite components in a pebble-bed nuclear reactor caused by the moving fuel balls and, thus, to help evaluate the integrity of the whole graphite structures over their service life. To this end, wear tests were conducted on the chewing machine with a specially designed load jig. The test specimens included graphite plates and graphite spheres, to represent the graphite bricks and fuel spheres, respectively. The main parameters, including volume loss of graphite plates and spheres, micro-morphology of the wear surface and weight and particle size of graphite dust generated, were studied in this work.