Abstract: An article for magnetic heat exchange includes a functionally-graded monolithic sintered working component including La1-aRa(Fe1-x-yTyMx)13HzCb with a NaZn13-type structure. M is one or more of the elements from the group consisting of Si and Al, T is one or more of the elements from the group consisting of Mn, Co, Ni, Ti, V and Cr and R is one or more of the elements from the group consisting of Ce, Nd, Y and Pr. A content of the one or more elements T and R, if present, a C content, if present, and a content of M varies in a working direction of the working component and provides a functionally-graded Curie temperature. The functionally-graded Curie temperature monotonically decreases or monotonically increases in the working direction of the working component.

Abstract: An article for magnetic heat exchange includes a functionally-graded monolithic sintered working component including La1-aRa(Fe1-x-yTyMx)13HzCb with a NaZn13-type structure. M is one or more of the elements from the group consisting of Si and Al, T is one or more of the elements from the group consisting of Mn, Co, Ni, Ti, V and Cr and R is one or more of the elements from the group consisting of Ce, Nd, Y and Pr. A content of the one or more elements T and R, if present, a C content, if present, and a content of M varies in a working direction of the working component and provides a functionally-graded Curie temperature. The functionally-graded Curie temperature monotonically decreases or monotonically increases in the working direction of the working component.

Abstract: An article for magnetic heat exchange includes a functionally-graded monolithic sintered working component including La1-aRa(Fe1-x-yTyMx)13HzCb with a NaZn13-type structure. M is one or more of the elements from the group consisting of Si and Al, T is one or more of the elements from the group consisting of Mn, Co, Ni, Ti, V and Cr and R is one or more of the elements from the group consisting of Ce, Nd, Y and Pr. A content of the one or more elements T and R, if present, a C content, if present, and a content of M varies in a working direction of the working component and provides a functionally-graded Curie temperature. The functionally-graded Curie temperature monotonically decreases or monotonically increases in the working direction of the working component.

Abstract: An article for magnetic heat exchange comprising a magnetocalorically active phase with a NaZn13-type crystal structure is provided by hydrogenating a bulk precursor article. The bulk precursor article is heated from a temperature of less than 50° C. to at least 300° C. in an inert atmosphere and hydrogen gas only introduced when a temperature of at least 300° C. is reached. The bulk precursor article is maintained in a hydrogen containing atmosphere at a temperature in the range 300° C. to 700° C. for a selected duration of time, and then cooled to a temperature of less than 50° C.

Abstract: A process of fabricating a monolithic working component for magnetic heat exchange is disclosed. The process includes mixing two or more portions comprising amounts of La, Fe, Si and at least one of T and R suitable to produce a La1-aRa(Fe1-x-yTySix)13Hz phase, wherein T is at least one element from the group consisting of Mn, Co, Ni and Cr and R is at least one element from the group consisting of Ce, Nd, Y and Pr. The amount of T, R, and Si is selected for each of the two or more portions to provide the two or more portions with differing Curie temperatures and, preferably, a density, d, within a range of ±5% of an average density, dav, of a total number of portions. The process includes heat treating a single monolithic green body formed from two or more precursor powder mixtures to produce a single monolithic working component.

Abstract: An article for magnetic heat exchange includes a functionally-graded monolithic sintered working component including La1-aRa(Fe1-x-yTyMx)13HzCb with a NaZn13-type structure. M is one or more of the elements from the group consisting of Si and Al, T is one or more of the elements from the group consisting of Mn, Co, Ni, Ti, V and Cr and R is one or more of the elements from the group consisting of Ce, Nd, Y and Pr. A content of the one or more elements T and R, if present, a C content, if present, and a content of M varies in a working direction of the working component and provides a functionally-graded Curie temperature. The functionally-graded Curie temperature monotonically decreases or monotonically increases in the working direction of the working component.

Abstract: An article for magnetic heat exchange comprising a magnetocalorically active phase with a NaZn13-type crystal structure is provided by hydrogenating a bulk precursor article. The bulk precursor article is heated from a temperature of less than 50° C. to at least 300° C. in an inert atmosphere and hydrogen gas only introduced when a temperature of at least 300° C. is reached. The bulk precursor article is maintained in a hydrogen containing atmosphere at a temperature in the range 300° C. to 700° C. for a selected duration of time, and then cooled to a temperature of less than 50° C.

Abstract: An article for magnetic heat exchange comprises a monolithic working component comprising two or more portions. The two or more portions comprise amounts of La, Fe, Si and of one or more elements T and R suitable to produce a La1-aRa(Fe1-x-yTySix)13Hz phase, wherein T is one or more of the elements from the group consisting of Mn, Co, Ni and Cr and R is one or more of the elements from the group consisting of Ce, Nd, Y and Pr. The amount of the one or more elements T and R and the amount of Si is selected for each of the two or more portions to provide the two or more portions with differing Curie temperatures and, preferably, a density, d, within a range of ±5% of an average density, dav, of a total number of portions.

Abstract: A working component for magnetic heat exchange comprises a magnetocalorically active phase comprising La1-aRa(Fe1-x-yTyMx)13Hz, a hydrogen content, z, 90% or higher of a hydrogen saturation value, zsat, and values of a, x and y selected to give a Curie temperature Tc. M is one or more of the elements from the group consisting of Al and Si, T is one or more of the elements from the group consisting of Co, Ni, Mn, Cr, Cu, Ti and V and R is one or more of the elements from the group consisting of Ce, Nd, Y and Pr. Tcmax is a Curie temperature of a La1-aRa(Fe1-x-yTyMx)13Hz phase comprising a hydrogen content z=zsat and said selected values of a, x and y. The working component comprises the Tc wherein (Tcmax?Tc)?20K.

Abstract: A method for the production of pressed permanent magnets comprises the following steps: A mixture of at least one magnetic powder and a thermosetting binder is provided and pressed to produce a moulded body. In order to obtain a permanent and particularly reliable protection against oxidation and corrosion, the moulded body is impregnated with an acid and solvent mixture in an impregnating bath before the cure of the thermosetting binder, whereby the entire surface of the permanent magnet is coated with a reaction layer [FIG. 1].

Abstract: An article for magnetic heat exchange comprising a magnetocalorically active phase with a NaZn13-type crystal structure is provided by hydrogenating a bulk precursor article. The bulk precursor article is heated from a temperature of less than 50° C. to at least 300° C. in an inert atmosphere and hydrogen gas only introduced when a temperature of at least 300° C. is reached. The bulk precursor article is maintained in a hydrogen containing atmosphere at a temperature in the range 300° C. to 700° C. for a selected duration of time, and then cooled to a temperature of less than 50° C.

Abstract: Article for use in magnetic heat exchange, intermediate article and method for producing an article for use in magnetic heat exchange An article for magnetic heat exchange is produced by heat treating an intermediate article comprising, in total, elements in amounts capable of providing at least one magnetocalorically active LaFe13-based phase and less than 5 Vol % impurities, wherein the intermediate article comprises a permanent magnet. The intermediate article is worked by removing at least one portion of the intermediate article. The intermediate article is then heat treated to produce a final product comprising at least one magnetocalorically active LaFe13-based phase.

Abstract: A method for the production of pressed permanent magnets comprises the following steps: A mixture of at least one magnetic powder and a thermosetting binder is provided and pressed to produce a moulded body. In order to obtain a permanent and particularly reliable protection against oxidation and corrosion, the moulded body is impregnated with an acid and solvent mixture in an impregnating bath before the cure of the thermosetting binder, whereby the entire surface of the permanent magnet is coated with a reaction layer [FIG. 1].

Abstract: The invention relates to a method for producing rod-shaped permanent magnets according to which pressed parts (2) are produced that are then assembled to a rod-shaped green product. Said green product is subsequently sintered, whereby a rod-shaped single-piece permanent magnet (1) is produced.

Abstract: According to the inventive method for producing a composite part (4), a support body (1) is produced from a powder with a ferrous alloy base using powder metallurgy. A magnet body (2) which is based on an alloy that is rich in rare earths is applied to the support body (1) and both are then sintered in a furnace (1), whereby a solid joint is formed between the support body (1) and the magnet body (2).

Abstract: The invention relates to a method for producing rod-shaped permanent magnets according to which pressed parts (2) are produced that are then assembled to a rod-shaped green product Said green product is subsequently sintered, whereby a rod-shaped single-piece permanent magnet (1) is produced.