Elastocaloric effect vs fatigue life
exploring the durability limits of Ni-Ti plates under pre-strain conditions for elatocaloric coolling
Povzetek
Structural fatigue is the major obstacle that prevents practical applications of the elastocaloric effect (eCE) in cooling or heat-pumping devices. Here, the eCE and fatigue behaviour of Ni-Ti plates are systematically investigated in order to define the fatigue strain limit and the associated eCE. Initially, the eCE was evaluated by measuring adiabatic temperature changes at different strain amplitudes and different mean strains along the loading and unloading transformation plateaus. By comparing the eCE with and without pre-strain conditions, the advantages of cycling an elastocaloric material at the mean strain around the middle of the transformation plateau were demonstrated. In the second part of this work, we evaluated the fatigue life at the mean strain of 2.25% at the loading plateau and at the unloading plateau after initial pre-straining up to 6% and 10%, respectively. It is shown that on polished samples, durable operation of 10 5 cycles can be reached with a strain amplitude of 0.50% at the loading plateau, which corresponds to adiabatic temperature changes of approximately 5 K. At the unloading plateau (after initial pre-strain of 10%), durable operation was reached at a strain amplitude of 1.00%, corresponding to adiabatic temperature changes of approximately 8%K. The functional fatigue was analysed after the cycling and it is shown that once the sample has been stabilized there is no further degradation of the eCE, even after 10 5 cycles. These results present guidelines for the design and operation of efficient and durable elastocaloric devices in the future.
Ključne besede
elastokalorični učinek;utrujanje;materiali z oblikovnim spominom;elastocaloric effect;fatigue;shape memory materials;
Podatki
| Jezik: | Angleški jezik |
|---|---|
| Leto izida: | 2018 |
| Tipologija: | 1.01 - Izvirni znanstveni članek |
| Organizacija: | IMT - Inštitut za kovinske materiale in tehnologije |
| UDK: | 621.56(045) |
| COBISS: |
15964187
|
| ISSN: | 1359-6454 |
| Št. ogledov: | 303 |
| Št. prenosov: | 157 |
| Ocena: | 0 (0 glasov) |
| Metapodatki: |
|
Ostali podatki
| Sekundarni jezik: | Slovenski jezik |
|---|---|
| Sekundarne ključne besede: | elastokalorični učinek;zlitine z oblikovnim spominom;Ni-Ti;utrujanje;deformacije; |
| Vrsta dela (COBISS): | Članek v reviji |
| Konec prepovedi (OpenAIRE): | 2020-03-22 |
| Strani: | str. 295-307 |
| Zvezek: | ǂVol. ǂ150 |
| Čas izdaje: | May 2018 |
| DOI: | 10.1016/j.actamat.2018.03.032 |
| ID: | 13077187 |
Priporočena dela:
Elastocaloric effect vs fatigue life
2018,
exploring the durability limits of Ni-Ti plates under pre-strain conditions for elatocaloric coolling
ǂA ǂregenerative elastocaloric device
2017,
experimental results
ǂA ǂregenerative elastocaloric heat pump
2016,
ni podatka o podnaslovu
Optimiranje učinkovitosti elastokaloričnih materialov z mehanskim obremenjevanjem pri različnih temperaturah
2019,
magistrsko delo magistrskega študijskega programa II. stopnje Strojništvo
Understanding the thermodynamic properties of the elastocaloric effect through experimentation and modelling
2016,
ni podatka o podnaslovu