Magnetostriction and Magnetocaloric Effect in Mn1 – Xfexas Alloys

Some results of studying the temperature dependence of the magnetocaloric effect ΔТad, thermal expansion, and magnetostriction in the Mn1 – хFexAs system (х = 0.003, 0.006) in magnetic fields up to 8 T are presented. It has been shown that an increase in the iron concentration in the Mn1 – хFexAs system leads to the shift of the phase transition temperature towards lower values by 15 K. In a field of 8 T, ΔТad = 8.3 K for Mn0.997Fe0.003As at an initial temperature T0 = 318 K, and ΔТad = 7.7 K for Mn0.994Fe0.006As at T0 = 307 K. The thermal expansion and magnetostriction data show that the magnetostriction decreases with increasing iron concentration, which also leads to a decrease in the magnetocaloric effect.