26 KB151 KB20 KB200020242010Batistić, IvoBihar, ŽeljkoBilušić, AnteLeontić, BoranLukatela, JagodaPopčević, PetarSmiljanić, IgorSmontara, AnaStanić, Denisštevilka:1letnik:44str. 3-7ISSN:1580-2949COBISSID:795050URN:URN:NBN:SI:doc-AXALMXRVenInštitut za kovinske materiale in tehnologijeMateriali in tehnologijekompleksne kovinske zlitinespektralna prevodnosttoplotna prevodnostThe thermal conductivity of Alsub{73}Mnsub{27-x}Fesubx Taylor phases| Toplotna prevodnost Taylorjevih faz Alspodaj{73}Mnspodaj{27-x}Fespodajx|The thermal conductivity (k) of Alsub{73}Mnsub{27-x}Fesubx (x = 0, 2, 4, 6) complex metallic alloys has been measured in the temperature interval from 2 K to 300 K. All the alloys are Tylor (T) phases, except Alsub{73}Mnsub{21}Fesub6, which is a decagonal (d) quasicrystal. The behaviours of k are typical for complex metallic alloys, i.e., a relatively small magnitude, a change of slope at about 50 K and an increase of the conductivity above 100 K. At room temperature the magnitude of k for all the samples is between 2.7 W/mK and 3.3W/mK, which is comparable to that of thermally insulating amorphous SiOsub SiOsub2 and Zr/YOsub2 ceramics. The reason for such a low thermal conductivity is because both, the electronic and lattice conductivity are low. The electronic contribution to the thermal conductivity is low because of the large electrical resistivity of the samples. The lattice thermal conductivity is greatly reduced because of the enhanced umklapp process of the phonon scattering (caused by the large lattice constant) and by the disorder in the structureToplotna prevodnost (k) kompleksnih kovinskih zlitin Alspodaj{73}Mnspodaj{27-x}Fespodajx (x = 0, 2, 4, 6) je bila izmerjena v razponu temperatur od 2 K do 300 K. Vse zlitine, z izjemo Alspodaj{73}Mnspodaj{21}Fespodaj6, ki je dekagonalni (d) kvazikristal, so Taylorjeve (T) faze. Vedenje toplotne prevodnosti k je značilno za kompleksne kovinske zlitine: relativno majhna velikost, sprememba naklona pri približno 50 K in povečana prevodnost nad 100 K. Pri sobni temperaturi je velikost k za vse preizkušance med 2,7 in 3,3 W/mK, kar je primerljivo s toplotno izolirno amorfno SiOspodaj2- in Zr/YOspodaj2-keramiko. Vzrok za tako majhno toplotno prevodnost stamajhni elektronska in mrežna prevodnost. Elektronski prispevek k toplotni prevodnosti je majhen zaradi velike električne upornosti zlitin. Mrežna toplotna prevodnost je zmanjšana zaradi povečanja procesa "umklapp" razpršitve fononov (zaradi velikega parametra mreže) in nereda v strukturiTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaInštitut za kovinske materiale in tehnologije