17 KB228 KB15 KB200020242011Bílek, PavelJurči, PeterSobotová, Janaletnik:45številka:5str. 489-493ISSN:1580-2949COBISSID:882346URN:URN:NBN:SI:doc-7UPCXIEFenInštitut za kovinske materiale in tehnologijeMateriali in tehnologijekaljenjekarbidiledeburitna jeklamikrostrukturaorodna jeklaEvaluation of the microstructural changes in Cr-V ledeburitic tool steels depending on the austenitization temperature| Ocena sprememb mikrostrukture v ledeburitnem orodnem jeklu Cr-V v odvisnosti od temperature avstenitizacije|Samples of Vanadis 6 PM Cr-V ledeburitic steel were austenitized at temperatures in the range 1000-1200 °C and oil-quenched. The structural changes were investigated by scanning electron microscope and evaluated using NIS Elements software. The obtained results indicated that the M7C3-carbides underwent intensive dissolution in austenite and were not detected above a temperature of 1100 °C. On the other hand, the MC-carbides remained almost completely unaffected and symptoms of dissolution were found only at a temperature of 1200 °C. The saturation of austenite by carbon, chromium and partly vanadium increased the hardness of the as-quenched material, with the maximum at an austenitizing temperature of 1025 °CVzorci ledeburitnega jekla Cr-V Vanadis 6 PM so bili avstenitizirani v temperaturnem območju 1000-1200 °C in kaljeni v olju. Spremembe mikrostrukture so bile raziskane z vrstičnim elektronskim mikroskopom in ocenjene z uporabo NIS-elementnega softvera. Rezultati kažejo, da so se karbidni M7C3 hitro raztapljali v avstenitu in jih ni bilo opaziti nad temperaturo 1100 °C. Po drugi strani so VC-karbidi ostali nespremenjeni, a simptome raztapljanja smo opazili le pri temperaturi 1200 °C. Nasičenje avstenita z ogljikom, kromom in delno vanadijem je povečalo trdoto kaljenega materiala z maksimumom pri temperaturi 1025 °CTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaInštitut za kovinske materiale in tehnologije