22 KB840 KB20 KB200020242010Anđić, ZoranJovanić, PredragTasić, MilošVujović, A ...letnik:44številka:6str. 397-401ISSN:1580-2949COBISSID:843690URN:URN:NBN:SI:doc-EKAMGRKPenInštitut za kovinske materiale in tehnologijeMateriali in tehnologijeakustična emisijakontinuirno litjekristalizacijamakrostrukturamedeninaneporušne preiskavestrjevanjeAnalysis of the process of crystallization of continuous cast special brass alloys with the acoustic emission| Analiza procesa kristalizacije kontinuirno lite specialne medenine z metodo akustične emisije|Analyses of possibilities of monitoring the crystallization process of continuously cast special brass alloys with acoustic emission and for establishing a correlation between the microstructure and the recorded acoustic emission signals. With appropriate selection of parameters for gravitational casting process, continuous casting was performed and samples with a macrostructure typical of continuous casting were obtained. A laboratory plant for the simulation of the continuous casting and for the analysis of the crystallization process with acoustic emission was designed. Different energy levels in samples with different macrostructure, as well as in the defective and non-defective samples, were observed. Two types of sources of signals were defined: the signal during solidification of correct crystallization and macrostructure of continuous casting and acoustic emission signal during solidification of samples in with flaws. To check the obtained results, after completion of the crystallization process, the samples were submitted to external with mechanical loading. The acoustic activity by loading is in accordance with the results of on-line monitoring ofthe crystallization process with acoustic emission. The results obtained show that it is possible to use the acoustic emission for monitoring the crystallization process by continuous and gravitational castingRaziskava je namenjena možnosti za spremljanje procesa kristalizacije kontinuirne lite posebne medenine z metodo akustične emisije in opredelitvi povezave med makrostrukturo in zabeleženimi signali akustične emisije. S primerno izbiro parametrov procesa gravitacijskega litja je bilo izvršeno kontinuirno litje in dobljeni so bili vzorci s tipično makrostrukturo tega litja. Pripravljen je bil tudi načrt za napravo za laboratorijsko simulacijo kontinuirnega litja in analizo procesa kristalizacije z akustično emisijo. Opaženi so bili različni nivoji energije v vzorcih za različno makrostrukturo in vzorci brez napak in z njimi. Rezultat raziskave je bila definicija dveh izvirov signalov akustične emisije: signal med strjevanjem s pravilno kristalizacijo in makrostrukturo in signal med strjevanjem vzorcev, v katerih nastajajo napake. Zaradi preverjanja dobljenih rezultatov so bili vzorci po končani kristalizaciji izpostavljeni zunanji indukciji makrostrukture z mehansko obremenitvijo. Akustična emisija med to obremenitvijo je skladna z rezultati spremljanja procesa kristalizacije z akustično emisijo. Sklep je, daje mogoča uporaba akustične emisije za spremljanje kristalizacije pri neprekinjenem gravitacijskem litjuTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaInštitut za kovinske materiale in tehnologije