40 KB537 KB32 KB200020262012Aleksandrović, SrbislavLazić, VukićMilosavljević, DraganMutavdžić, MilanNikolić, IlijaNikolić, RužicaSedmak, Aleksanderletnik:46številka:5str. 547-554ISSN:1580-2949COBISSID:946090URN:URN:NBN:SI:doc-UNHIFCAVenInštitut za kovinske materiale in tehnologijeMateriali in tehnologijeaustenite steelavstenitno jeklohard facingmining engineering equipmentnanašanje trdih prevlekorodno jeklorudarska strojna oprematool steeltrde prevlekeTheoretical and experimental estimation of the working life of machine parts hard faced with austenite-manganese electrodes| Teoretično in eksperimentalno ugotavljanje zdržljivosti strojnih delov, oplaščenih s trdimi avstenitno-manganskimi elektrodami|We have investigated the possibility of repairing damaged machine parts by hard facing with austenite-manganese steel electrodes. The subject is a Fe-C-Mn alloy with a microstructure of soft austenite which, after cold deformation, transforms by a shearing mechanism into a hard martensite microstructure. These steels are used mainly for parts exposed to high impact loads and intensive abrasive wear. Depending on the degree of wear, these parts can be replaced by new ones or repaired by hard facing. The selection of the optimal reparation technology for the rotational crusher's impact beams is the subject of this study. Investigations of model samples were conducted first, followed by layers hard faced onto samples with austenite manganese and special electrodes. After this the microstructure and hardness of the welds' characteristic zones were investigated. After reparatory hard facing the impact beams were mounted in the crusher and their behaviour was monitored periodically. Both the new and hard-faced beams' behaviours were monitored and compared under the same working conditions. In this way, the optimal technology for hard facing was established, taking into account not only the technical indicators, but also the economic effectsTa članek predstavlja študij možnosti obnove poškodovanih delov z nanašanjem trdih plasti iz avstenitno-manganskih jekel. Predmet raziskave je zlitina Fe-C-Mn z mehko avstenitno mikrostrukturo, ki se med hladno deformacijo s strižnimi mehanizmi pretvori v trdo martenzitno mikrostrukturo. Ta jekla se uporabljajo predvsem za dele, izpostavljene velikim udarnim obremenitvam in močni obrabi. Odvisno od stopnje obrabe se ti deli nadomeščajo z novimi ali pa se obnovijo s trdimi nanosi. V tem delu je preučevana izbira optimalne tehnologije obnove rotacijskih udarnih drobilnikov. Najprej je bila izvršena preiskava na modelnih vzorcih z nanosom trde plasti iz avstenitno-manganske posebne elektrode, nato pa preiskana še mikrostruktura in trdota značilnih varjenih področij. Po obnovi z nanosom trde plasti so bile udarne plošče nameščene v drobilnik in periodično je bilo spremljano njihovo vedenje. Primerjane so bile lastnosti novih in obnovljenih plošč v enakih obratovalnih razmerah. Tako je bila določena optimalna tehnologija obnavljanja delov z upoštevanjem ne samo tehničnih lastnosti, temveč tudi iz ekonomskega stališčaTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaInštitut za kovinske materiale in tehnologije