Active Magnetic Regeneration - Magnetocaloric Energy Conversion: From Theory to Applications - page 153

Fig. 4.35 a AMR with spacers integrated into the housing. b Jointed AMR

Fig. 4.36 A photograph of a laser-welded AMR with a plate thickness of 0.25 mm

spacings can be joined by gluing [ 132 ] or laser welding [ 101 ] see Fig. 4.36 . The

laser welding of the AMR is especially interesting since it enables a precise and
permanent joint of an arbitrary thin spacer and the magnetocaloric plate, and is
further insensitive to the working

—

uid. The spacer must, of course, be weldable,
with the magnetocaloric material used (for example gadolinium and stainless steel
as a spacer are compatible).

fl

4.7.2 Fabrication of Powder-Based (sintered) AMRs

The magnetocaloric materials produced by powder metallurgy, e.g. La-based and
Mn-based materials, require special forming and processing techniques for the
AMR

s fabrication [ 133 ]. The great majority of these types of materials were tested in
the form of a powder in packed-bed AMRs [ 5 ]. However, some fabrication methods
for producing powder-based ordered AMRs were presented and evaluated as well.

'