20.500.12556/DKUM-57937 Vpliv staranja na mehanske lastnosti smolno vezanih brusov s korundnimi in SiC zrni The impact of ageing to mechanical characteristics of reisn bonded wheels V doktorski disertaciji smo na osnovi preizkusov, izvedenih na smolno vezanih brusih s korundnimi zrni in zrni silicijevega karbida (SiC), ugotavljali, kako v določenih časovnih zaporedjih staranje vpliva na njihove mehanske in funkcionalne lastnosti. Na osnovi meritev smo oblikovali časovni model poteka sprememb. Pravilnost pristopa zastavljenega koncepta raziskav, s katerim smo zagotovili zanesljivost in ponovljivost izvedenih meritev, smo potrdili z oceno vrednosti Weibullovega modula. Prav tako smo preverili in ugotavljali vpliv vlage kot najverjetnejšega povzročitelja hitrejšega padca mehanskih lastnosti brusov. V tem kontekstu smo uporabili sistem vsiljenega, t.j. hitrejšega staranja brusov (dodatno vlaženje) pri atmosferskih pogojih. V nadaljevanju smo na osnovi karakterizacije mikrostruktur brusov, ki so bili izpostavljeni različnim termomehanskim vplivom, izdelali modele mehanizmov spreminjanja mikrostruktur med staranjem. Ti so potrdili že empirično ugotovljen najverjetnejši razlog vpliva na staranje in s tem povezanih sprememb mehanskih lastnosti brusov. Ugotovitve smo z reverzibilnim procesom termične obdelave tudi potrdili. Spoznanja so praktično uporabna v procesu proizvodnje brusov, omogočajo izboljšanje mehanskih lastnosti, predvsem pa bistveno upočasnijo proces staranja in s tem dajo brusu višjo dodano vrednost. The doctoral dissertation seeks to identify the manner in which ageing affects the mechanical and functional properties of resin-bonded grinding wheels with aluminium oxide and silicon carbide in certain time series based on the tests performed. The measurements provided the basis for the design of a temporal model of changes. The regularity of the approach used in the set research concept, which provided reliable and reproducible measurements, was confirmed with an assessment of the value of the Weibull modulus. Furthermore, the influence of humidity as the most likely cause for a steep downgrade in the mechanical properties of grinding wheels was examined and identified. Within that context, the system of forced, i.e. accelerated ageing of grinding wheels (additional humidification) was used under special atmospheric conditions. In the continuation, model mechanisms for changing microstructures during ageing were produced based on the microstructure characterization of grinding wheels that were exposed to different thermo mechanical impacts. These confirmed the most likely cause for ageing as established empirically and therewith related changes to the mechanical properties of grinding wheels. The findings were confirmed with a reversible thermal treatment process. Furthermore, the findings are useful in practice, i.e. in the process of manufacturing grinding wheels, allow for improvements to mechanical properties and, most of all, considerably slow down the ageing process, thus giving such products higher added value. smolno vezani brusi mehanske lastnosti natezna trdnost statistične metode staranje mikroskopska analiza vzorcev brusov resin-bonded grinding wheels mechanical properties tensile strength statistical methods ageing microscopic analysis of grinding wheel samples true true false [A. Matavž] Slovenski jezik Angleški jezik Doktorsko delo/naloga 2016-03-30 08:51:29 2016-09-08 10:07:46 2022-06-15 03:09:44 2019-07-11 10:23:08 2016 0 Maribor 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 2019-09-08 621.922:621.924.9(043.3) 19765270 URN:SI:UM:DK:PEDD6A6N EDOK_Matavz_Albin_2016.pdf EDOK_Matavz_Albin_2016.pdf 1 F0942C2B27CFABDC144F3567B48D3A42 de9d95fe8aea9de7086aa90fcb3bbcbc515c0071d2c293036cd3faa8ad42b20b 325cf924-7c0d-11eb-bb7a-00155d0001ca https://dk.um.si/Dokument.php?lang=slv&id=101048 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0