A new feature of the reduction-diffusion process applied for the synthesis of magnetocaloric LaFe13-xSix compounds

作者：Teixeira C S^*; Caron L; Anastasopol A; Eijt S W H; Lozano J A; Bruck E; Wendhausen P A P

来源：Journal of Alloys and Compounds, 2012, 541: 84-87.

DOI：10.1016/j.jallcom.2012.05.112

• Magnetocaloric effect
• LaFe13-xSix
• Hydrogenation
• Calciothermic reduction-diffusion

The feasibility of a powder metallurgical route based on the reduction-diffusion (R/D) process to synthesize LaFe13 Si-x(x) magnetocaloric compounds is shown. The reaction products, characterized via scanning electron microscopy and X-ray diffraction, show large amounts of the LaFe13 Si-x(x) main phase and lower contents of secondary non-desired phases, such as alpha-(Fe, Si). A remarkable increase in the Curie temperature (T-C) of the magnetocaloric phase after a lixiviation step, necessary to remove reaction by-products, was also investigated. Clear evidences of this change in T-C by interstitial modification due to in-situ hydrogenation are reported, based on hydrogen desorption experiments supported by mass-spectrometry, X-ray diffraction and thermomagnetic characterization.

• 出版日期2012-11-15