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Herein, the magnetic properties and elastocaloric effects of Cu70Al19 + 0.5xMn11−0.5x (x = 0, 1, 2, 3) alloys are investigated. The resistance versus temperature curves indicate that the phase transition temperature increases as the Mn content decreases. In particular, the Cu70Al20.5Mn9.5 alloy exhibits a phase transition temperature close to room temperature. Therefore, the elastocaloric effects of this alloy are examined under stresses ranging from 200 to 500 MPa. The results show that the adiabatic temperature change of the alloy under a stress of 500 MPa reaches 9.8 K. Furthermore, the magnetization curves at 300 K reveal that the magnetic properties of the alloy significantly improve after undergoing low‐temperature aging treatment. The X‐ray diffraction patterns show that this improvement can be attributed to the transformation of the β1 phase to the ferromagnetic phase β3. Overall, the Cu70Al20.5Mn9.5 alloy demonstrates elastocaloric and magnetic properties comparable to those observed in certain Ni–Mn‐based alloys. [ABSTRACT FROM AUTHOR]

The effect of hydrostatic pressure on the martensitic transformation and magnetocaloric properties of MnNi0.88GeV0.12 alloy is studied in detail. X‐ray diffraction at room temperature shows that the alloy has a single hexagonal Ni2In‐type structure. The phase transition temperature moves to the low‐temperature region with the increase in hydrostatic pressure. Under the external magnetic field of 15 kOe, the hydrostatic pressure driving rates dTM/dP and dTA/dP are 60.25 and 65.25 K GPa−1, respectively, which indicate that the applied pressure expands the working temperature range of magnetic refrigeration. A magnetic entropy change ΔS of −4.8 J kg−1 K−1 is obtained in the external magnetic field of 15 kOe under ambient pressure. The peak value of |ΔS| is increased to 5.6 J kg−1 K−1 under hydrostatic pressure, which is closely related to the structural change of the alloy. [ABSTRACT FROM AUTHOR]

The co-influence of B and Si on the formation of 1:13 phase and corrosion behavior of LaFe 13 − x Si x B y alloys is investigated. 1:13 phase is found in as-cast LaFe 11.6 Si 1.4 B 0.5 , while there is no 1:13 phase in as-cast LaFe 12.0 Si 1.0 B 0.5 with lower Si content. The addition of B in the LaFe 13 − x Si x B y alloys is not helpful for the formation of 1:13 phase during the annealing process. B element prefers to form Fe 2 B, rather than occupying interstitial sites in the crystal structure of 1:13 phase, which results in the decrease of the value of magnetic entropy change (| Δ S |). Corrosion behaviors of annealed LaFe 11.6 Si 1.4 B y alloys are reported. The results show that the addition of B improves the corrosion resistance of the alloys. Polarization curves of single phase α -Fe, Fe 2 B and 1:13 phase show that the potential difference between Fe 2 B and 1:13 phase is lower than that between α -Fe and 1:13 phase, which lead to the enhancement of corrosion resistance. The corrosion of LaFe 11.6 Si 1.4 B 0.3 is effectively suppressed, and the value of | Δ S | is only reduced by 28%. [ABSTRACT FROM AUTHOR]