Effect of Fe addition on microstructure and magnetocaloric effect in Gd(5)Si(x)Ge(3.9-x)Fe(0.1) alloys with varying Si/Ge ratio

Abstract

The Gd(5)Si(x)Ge(3.9-5)Fe(0.1) alloys (x = 1.8-2.1) alloys exhibited a first-order magnetic phase transition with hysteresis of 8-13 K upon heating and cooling. Microstructural studies revealed that the alloys were comprised of monoclinic Gd(5)Si(2)Ge(2)-type phase with small fraction of the Gd(5)Si(3)-type and FeSi-rich minor phases. The hysteresis losses are significantly reduced in the x = 2.1 alloy due to the absence of field-induced phase transition. (C) 2009