Phase transitions and magnetic entropy change in Mn-rich Ni-Mn-Ga alloys

Magnetocaloric properties of Mn-rich compounds in the vicinity of the co-occurrence of magnetic and structural transitions were investigated. Polycrystalline samples with nominal compositions ranging from Ni/sub 47.5/Mn/sub 33.5/Ga/sub 20/ to Ni/sub 50/Mn/sub 30/Ga/sub 20/ were prepared by arc melting technique. Sample composition, structure, martensitic and Curie transition temperatures were determined by energy dispersion spectrometry, X-ray diffraction and thermomagnetic analysis.