Composite article with magnetocalorically active material and method for its production
View Patent ↗A composite article ( 1; 10; 40 ) comprises a plurality of inclusions ( 5 ) of a magnetocalorically active material embedded in a matrix ( 4 ) of a magnetocalorically passive material. The inclusions ( 5 ) and the matrix ( 4 ) have a microstructure characteristic of a compacted powder.
1. A method of manufacturing a solid composite article, comprising:
providing a first powder comprising a magnetocalorically active material,
providing a second powder comprising a magnetocalorically passive material,
mixing the first powder and the second powder together to form a powder mixture, and
compacting the powder mixture to form a solid composite article comprising a solid matrix comprising the magnetocalorically passive material and a plurality of solid inclusions comprising a magnetocalorically active material at least partially embedded in the solid matrix,
wherein the second powder comprises a plurality of particles which have been coated with an electrically isolating material before mixing the second powder with the first powder.
2. A method according to claim 1 , further comprising: adding one or more of a lubricant, an organic binder or a dispersant to the powder mixture.
3. A method according to claim 1 , wherein the first powder comprises a plurality of particles which are have been coated with a metallic corrosion protection coating before mixing the first powder with the second powder.
4. A method according to claim 1 , wherein the first powder comprises a plurality of particles which have been coated with an electrically isolating material before mixing the first powder with the second powder.
5. A method according to claim 1 , wherein the compacting is carried out under a pressure of 10 MPa to 3000 MPa.
6. A method according to claim 1 , wherein the powder mixture is compacted by one of the compacting comprises rolling or pressing.
7. A method according to claim 1 , wherein the compacting is carried out at room temperature or at a temperature between 30° C. to 250° C.
8. A method according to claim 1 , further comprising: heat treating the composite article after the compacting.
9. A method according to claim 8 , wherein the heat treating is carried out at a temperature between 300° C. and 1200° C. for a time between 2 hours and 10 hours.
10. A method according to claim 8 , wherein the heat treating is carried out under vacuum or in a protective atmosphere.
11. A method according to claim 1 , further comprising: compacting the composite article a second time.
12. A method according to claim 1 , further comprising: carrying out a finishing procedure.
13. A method of manufacturing a solid composite article, comprising:
providing a first powder comprising a magnetocalorically active material,
providing a second powder comprising a magnetocalorically passive material,
mixing the first powder and the second powder together to form a powder mixture,
compacting the powder mixture to form a solid composite article comprising a solid matrix comprising the magnetocalorically passive material and a plurality of solid inclusions comprising a magnetocalorically active material at least partially embedded in the solid matrix, and
coating a plurality of particles of the first powder and a plurality of particles of the second powder with an electrically isolating material after mixing the first powder with the second powder.
14. A method according to claim 13 , further comprising: adding one or more of a lubricant, an organic binder or a dispersant to the powder mixture.
15. A method according to claim 13 , wherein the first powder comprises a plurality of particles which are have been coated with a metallic corrosion protection coating before mixing the first powder with the second powder.
16. A method according to claim 13 , wherein the first powder comprises a plurality of particles which have been coated with an electrically isolating material before mixing the first powder with the second powder.
17. A method according to claim 13 , wherein the compacting is carried out under a pressure of 10 MPa to 3000 MPa.
18. A method according to claim 13 , wherein the powder mixture is compacted by one of the compacting comprises rolling or pressing.
19. A method according to claim 13 , wherein the compacting is carried out at room temperature or at a temperature between 30° C. to 250° C.
20. A method according to claim 13 , further comprising: compacting the composite article a second time.
21. A method according to claim 13 , further comprising: carrying out a finishing procedure.
22. A method of manufacturing a solid composite article, comprising:
providing a first powder comprising a magnetocalorically active material,
providing a second powder comprising a magnetocalorically passive material,
mixing the first powder and the second powder together to form a powder mixture,
compacting the powder mixture to form a solid composite article comprising a solid matrix comprising the magnetocalorically passive material and a plurality of solid inclusions comprising a magnetocalorically active material at least partially embedded in the solid matrix, and
enveloping the powder mixture in a mantle before compaction.
23. A method according to claim 22 , further comprising: adding one or more of a lubricant, an organic binder or a dispersant to the powder mixture.
24. A method according to claim 22 , wherein the first powder comprises a plurality of particles which are have been coated with a metallic corrosion protection coating before mixing the first powder with the second powder.
25. A method according to claim 22 , wherein the first powder comprises a plurality of particles which have been coated with an electrically isolating material before mixing the first powder with the second powder.
26. A method according to claim 22 , wherein the compacting is carried out under a pressure of 10 MPa to 3000 MPa.
27. A method according to claim 22 , wherein the powder mixture is compacted by one of the compacting comprises rolling or pressing.
28. A method according to claim 22 , wherein the compacting is carried out at room temperature or at a temperature between 30° C. to 250° C.
29. A method according to claim 22 , further comprising: compacting the composite article a second time.
30. A method according to claim 22 , further comprising: carrying out a finishing procedure.
31. A method of manufacturing a solid composite article, comprising:
providing a first powder comprising a magnetocalorically active material,
providing a second powder comprising a magnetocalorically passive material,
mixing the first powder and the second powder together to form a powder mixture,
compacting the powder mixture to form a solid composite article comprising a solid matrix comprising the magnetocalorically passive material and a plurality of solid inclusions comprising a magnetocalorically active material at least partially embedded in the solid matrix, and
applying an outer protective coating to the composite article.
32. A method according to claim 31 , wherein the applying of the outer protective coating comprises dipping, spraying, or electro-deposition.
33. A method according to claim 31 , wherein the applying of the outer protective coating occurs after a sintering heat treatment of the composite article.
34. A method according to claim 31 , wherein the applying of the outer protective coating occurs after compacting of composite article.
35. A method according to claim 31 , further comprising: adding one or more of a lubricant, an organic binder or a dispersant to the powder mixture.
36. A method according to claim 31 , wherein the first powder comprises a plurality of particles which are have been coated with a metallic corrosion protection coating before mixing the first powder with the second powder.
37. A method according to claim 31 , wherein the first powder comprises a plurality of particles which have been coated with an electrically isolating material before mixing the first powder with the second powder.
38. A method according to claim 31 , wherein the compacting is carried out under a pressure of 10 MPa to 3000 MPa.
39. A method according to claim 31 , wherein the powder mixture is compacted by one of the compacting comprises rolling or pressing.
40. A method according to claim 31 , wherein the compacting is carried out at room temperature or at a temperature between 30° C. to 250° C.
41. A method according to claim 31 , further comprising: compacting the composite article a second time.
42. A method according to claim 31 , further comprising: carrying out a finishing procedure.