Study of the Microstructure, Mechanical, and Magnetic Properties of LaFe11.6Si1.4Hy/Bi Magnetocaloric Composites

Abstract

We have successfully synthesized LaFe11.6Si1.4Hy/Bi composites by cold pressing together with vacuum annealing technology, and systematically investigated the microstructure, magnetism, mechanical performance, and magnetocaloric properties. LaFe11.6Si1.4Hy particles are well surrounded by metallic Bi, without the formation of new phase. The maximum values of the volumetric magnetic entropy change -ΔSM are as high as 51, 49, and 35 mJ/cm3K around 263 K, for the composites with 5, 10 and 15 wt % Bi contents, respectively. The maximum value of the compressive strength for LaFe11.6Si1.4Hy/Bi composites increased continuously from 155 to 358 MPa with increasing Bi content, from 0 to 15 wt %.

Comprehensive performance of a ball-milled La0.5Pr0.5Fe11.4Si1.6B0.2H y /Al magnetocaloric composite

“…As the Al content increases to 9 wt.%, the stress-strain diagram demonstrates typical characteristic of ductile materials, with a long yielding stage beginning at the yield strength of ∼ 44 MPa followed by a strain hardening process. This ductile mechanical behavior has not previously been observed in La(Fe,Si) 13 composites bonded by other ductile metals such as In, [4] Sn, [14] and Bi, [15] and is also absent in a LaFe 11 Co 0.8 Si 1.2 /10 wt.% Al composite prepared by the hot-pressing method. [6] The present 16.7 wt.% Al sample demonstrates an ultimate compressive strength of 388 MPa, much higher than the values for the hotpressed LaFe 11 Co 0.8 Si 1.2 /10 wt.% Al composite (186 MPa) and 20 wt.% Cu-bonded La 0.8 Ce 0.2 (Fe 0.95 Co 0.05 ) 11.8 Si 1.2 (248 MPa).…”

Adiabatic temperature change in ErAl2/metal PIT wires: A practical method for estimating the magnetocaloric response of magnetocaloric composites

“…For practical use of candidate materials, they are usually implemented in a refrigeration device as magnetic refrigerants after being processed into various shapes such as plates and spheres [4,16,17]. One way for shaping the candidate material is to use an additional non-magnetic substance as a binder [18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36], where the resulting material is a kind of magnetocaloric composites. On such an approach, one has to take care about how the magnetocaloric properties of both ∆S M and ∆T ad change before and after the processing.…”