Microstructural anisotropy of magnetocaloric gadolinium cylinders
effect on the mechanical properties of the material
Povzetek
The development of advanced materials and technologies based on magnetocaloric Gd and its compounds requires an understanding of the dependency of mechanical properties on their underlying microstructure. Therefore, the aim of the study was to characterize microstructural inhomogeneities in the gadolinium that can be used in magnetocaloric refrigeration systems. Microstructures of magnetocaloric gadolinium cylinders were investigated by light microscopy and FE-SEM (Field Emission Scanning Electron Microscopy), EDS (Energy-dispersive X-ray Spectroscopy), and BSE (Back-scattered Electrons) in both the extrusion and the extrusion-transversal directions. XRD (X-ray Diffraction) analyses were performed to reveal the presence of calcium- and fluorine-based compounds. Metallographic characterization showed an oxidized and inhomogeneous microstructure of the cross-sections. The edges and the outer parts of the cylinders were oxidized more intensively on the surfaces directly exposed to the processing tools. Moreover, a significant morphological anisotropy of the non-metallic inclusions was observed. CaF inclusions act as active nucleation sites for internal oxidation. The non-metallic, Ca- and F-containing inclusions can be classified as complex calciumoxyfluorides. The solubility of Er and Yb in the CaF was negligible compared to the Gd matrix and/or the oxide phase. Lower mechanical properties of the material are a consequence of the lower structural integrity due to selective oxidation of surfaces and interfaces.
Ključne besede
Gadolinium;magnetocaloric;inclusions;selective oxidation;mechanical porperties;
Podatki
| Jezik: | Angleški jezik |
|---|---|
| Leto izida: | 2016 |
| Tipologija: | 1.01 - Izvirni znanstveni članek |
| Organizacija: | UL FS - Fakulteta za strojništvo |
| UDK: | 620.1:67.017(045) |
| COBISS: |
1206698
|
| ISSN: | 1996-1944 |
| Št. ogledov: | 220 |
| Št. prenosov: | 59 |
| Ocena: | 0 (0 glasov) |
| Metapodatki: |
|
Ostali podatki
| Sekundarni jezik: | Slovenski jezik |
|---|---|
| Sekundarne ključne besede: | magnetokaloričnost;gadolinij;vključki;selektivna oksidacija;mehanske lastnosti; |
| Vrsta dela (COBISS): | Članek v reviji |
| Strani: | str. 1-14 |
| Letnik: | ǂVol. ǂ9 |
| Zvezek: | ǂiss. ǂ5 |
| Čas izdaje: | 2016 |
| DOI: | 10.3390/ma9050382 |
| ID: | 13582428 |
Priporočena dela:
Microstructural anisotropy of magnetocaloric gadolinium cylinders
2016,
effect on the mechanical properties of the material
Protective alumina coatings prepared by aerosol deposition on magnetocaloric gadolinium elements
2019,
ni podatka o podnaslovu
Evaluating magnetocaloric effect in magnetocaloric materials
2019,
ǂa ǂnovel approach based on indirect measurements using artificial neural networks
Nastanek poškodb v jeklu pri globokem vleku
2020,
magistrsko delo
Akustična emisija pri mehanskih preizkusih valjanih kovin
2018,
zaključna naloga univerzitetnega študijskega programa I. stopnje Strojništvo