Magnetostructural transition in Co-Mn-Ge systems tuned by valence electron concentration
Journal of Alloys and Compounds, cilt.791, ss.208-214, 2019 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 791
- Basım Tarihi: 2019
- Doi Numarası: 10.1016/j.jallcom.2019.03.048
- Dergi Adı: Journal of Alloys and Compounds
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
- Sayfa Sayıları: ss.208-214
- Anahtar Kelimeler: Martensitic transformation temperature, Magnetocaloric effect, Magnetic entropy change, Valence electron concentration, MAGNETIC PHASE-TRANSITION, MAGNETOCALORIC PROPERTIES, MARTENSITIC-TRANSFORMATION, DIAGRAM, MNCOGE
- Ankara Üniversitesi Adresli: Evet
Özet
© 2019 Elsevier B.V.The effects of annealing process and chemical pressure on the structural and magnetocaloric properties of CoMn1−xVxGe (x = 0.05 and 0.10) alloys have been studied. Rietveld refinement of XRD patterns revealed that all samples are single phase and they crystallize in hexagonal structure with a space group (P63/mmc) at room temperature. The structural phase transition temperature Tstruct decreases with increasing vanadium (V) content drastically in compare to CoMnGe alloy which exhibit a first order structural transition at around 450 K. The decrease in Tstruct. by substituting fourth element in CoMnGe-based alloys are discussed in frame of changing its valence electron concentration (e/a) values. We found that, alloys exhibiting a first order magneto-structural transition (FOMT) around room temperature, have an e/a value of 6.62–6.67. The e/a dependence of the magnetostructural transition temperature can be used as a guide to obtain an alloy with FOMT around room temperature.