Large Elastocaloric Effect Driven by Low Stress Induced in [001]-Oriented Polycrystalline Co51.6V31.4Ga17 Alloy

Abstract

In this work, we have studied the elastocaloric effect in directionally solidified Co51.6V31.4Ga17 alloys with a strong [001] preferred orientation. The entropy change for thermal-induced martensitic transformation is determined as 19.6 J kg−1 K−1. The sample exhibits stress-induced martensitic transformation with a hysteresis of 46 MPa, and the superelasticity is also verified by the in situ X-ray diffraction method. According to the elastocaloric effect tests, a noticeable change in adiabatic temperature up to 12.2 K has been achieved at the strain of 6%. The specific temperature change upon the critical stress loading can be attained as 132 K MPa−1. In addition, the difference in the loading–unloading temperature change can be ascribed to the imperfect adiabatic environment.