Superior properties of LaFe11.8Si1.2/La65Co35 magnetocaloric composites processed by spark plasma sintering

A series of LaFe11.8Si1.2/La65Co35 bulk composites were fabricated by spark plasma sintering (SPS) followed by diffusion annealing. The effect of sintering temperature (1073-1223 K) on the magnetocaloric and other properties of LaFe11.8Si1.2/La65Co35 bulk composites were investigated. The 1:13 phase content in all the annealed samples was similar to 90 wt%. The mechanical and magnetocaloric properties of these annealed bulk composites could be improved by tuning the sintering temperature. The Curie temperature (T-C) and maximum magnetic entropy change (-Delta S-M)(max) of the annealed samples varied in the range of 211-228 K and 5.56-9.33 J kg(-1) K-1, respectively. Selected samples exhibited excellent mechanical and magnetocaloric properties. The (-Delta S-M)(max) value was 9.33 J kg(-1) K-1 at TC of 217.8 K. Its maximum compressive strength (sigma(bc))(max) value was 540 MPa at a strain of 3.48%, which exceeded the mechanical properties of most LaeFeeSi based bulk composites prepared by hot- pressing sintering (HPS). Thus, LaeFeeSi based bulk composites with good comprehensive properties could be obtained by combining SPS and diffusion annealing. (c) 2022 The Author(s). Published by Elsevier B.V.

Automated summary

A series of LaFe11.8Si1.2/La65Co35 bulk composites were fabricated by spark plasma sintering (SPS) followed by diffusion annealing. The sintering temperature was found to have an effect on the mechanical and magnetocaloric properties of the composites. The annealed samples exhibited a 1:13 phase content of approximately 90 wt% and showed improved properties when the sintering temperature was adjusted.