20.500.12556/DKUM-27018 Microcrack initiation and growth in heat-risistant 15Kh2MFA steel under cyclic loading This paper presents the results of investigation of a nuclear reactor pressurevessel steel 15Kh2MFA of two strength levels under cyclic loading. Themechanism of microcrack formation on the surface and in the bulk of 15Kh2MFA steel under cyclic deformation was investigated. Analysis of the specimen surfaces has shown that microcracks are caused by cyclic sliding in grains most favourably oriented with respect to the direction of the maximum shear stresses. Transmission electron microscope investigations show that microcracks in the material inside the grains are formed mainly along the band-type dislocation structure parallel to the dislocation subboundary. During cyclic deformation, the dislocation density on the subboundaries increases, in the local areas the dislocation density becomes limiting and it reaches the plasticity limit and causes microcrack formation. The interrelation of the average length of microcracks and their surface density with the energy density of inelastic deformation has been found. material testing nuclear reactor pressure vessel cyclic loading cyclic deformation dislocation structure fatigue crack growth TEM fracture mechanics preizkušanje materialov jedrski reaktor tlačna posoda ciklično obremenjevanje ciklične deformacije struktura dislokacije utrujenostna razpoka rast razpoke lomna mehanika true false false Angleški jezik Angleški jezik Neznano 2012-06-01 09:38:22 2012-06-01 09:38:22 2022-04-15 03:43:11 2019-07-10 12:10:31 2005 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 621.1:539.42 9527574 8756-758X URN:SI:UM:DK:ZCH5KPAV http://dx.doi.org/10.1111/j.1460-2695.2005.00870.x 1 https://dk.um.si/Dokument.php?lang=slv&id=36253 Fakulteta za strojništvo 0 0 0