Method for fabricating a functionally-graded monolithic sintered working component for magnetic heat exchange and an article for magnetic heat exchange
First Claim
1. A method for fabricating a functionally-graded monolithic sintered working component for magnetic heat exchange, comprising:
- providing powder comprising elements in amounts sufficient for forming a La1-aRa(Fe1-x-yTyMx)13HzCb phase with a NaZn13 structure, wherein T is one or more of the elements selected from the group consisting of Mn, Co, Ni, Ti, V and Cr, M is one or more of the elements selected from the group consisting of Si and Al, and R is one or more of the elements selected from the group consisting of Ce, Nd, Y and Pr, wherein a is such that 0≤
a≤
0.5, b is such that 0≤
b≤
1.5, x is such that 0.05≤
x≤
0.2, y is such that 0≤
y≤
0.2, and z is such that 0≤
z≤
3;
forming the powder to provide a green body in which an amount of at least one element selected from the group consisting of T, R, C and M varies in a pre-determined direction of the green body,heat treating the green body at a temperature T and for a time t selected to allow diffusion of one or more of the elements selected from the group consisting of T, R and C, andthe heat treating step including forming a sintered working component comprising a Curie temperature that monotonically increases or monotonically decreases in the pre-determined direction, wherein the temperature T and the time t are selected to provide the monotonically increasing or monotonically decreasing Curie temperature, and wherein the monotonically increasing or monotonically decreasing Curie temperature changes with a gradient that lies within +/−
50% of a linear function over 80% of a length of the working component, wherein the linear function is defined as the difference between the Curie temperature at one end of the working component and the Curie temperature at the opposing end of the working component divided by the distance between the two ends, and wherein nowhere along the length of the working component is there a gradient that exceeds 10°
C./0.5 mm of length.
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Accused Products
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.
42 Citations
39 Claims
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1. A method for fabricating a functionally-graded monolithic sintered working component for magnetic heat exchange, comprising:
-
providing powder comprising elements in amounts sufficient for forming a La1-aRa(Fe1-x-yTyMx)13HzCb phase with a NaZn13 structure, wherein T is one or more of the elements selected from the group consisting of Mn, Co, Ni, Ti, V and Cr, M is one or more of the elements selected from the group consisting of Si and Al, and R is one or more of the elements selected from the group consisting of Ce, Nd, Y and Pr, wherein a is such that 0≤
a≤
0.5, b is such that 0≤
b≤
1.5, x is such that 0.05≤
x≤
0.2, y is such that 0≤
y≤
0.2, and z is such that 0≤
z≤
3;forming the powder to provide a green body in which an amount of at least one element selected from the group consisting of T, R, C and M varies in a pre-determined direction of the green body, heat treating the green body at a temperature T and for a time t selected to allow diffusion of one or more of the elements selected from the group consisting of T, R and C, and the heat treating step including forming a sintered working component comprising a Curie temperature that monotonically increases or monotonically decreases in the pre-determined direction, wherein the temperature T and the time t are selected to provide the monotonically increasing or monotonically decreasing Curie temperature, and wherein the monotonically increasing or monotonically decreasing Curie temperature changes with a gradient that lies within +/−
50% of a linear function over 80% of a length of the working component, wherein the linear function is defined as the difference between the Curie temperature at one end of the working component and the Curie temperature at the opposing end of the working component divided by the distance between the two ends, and wherein nowhere along the length of the working component is there a gradient that exceeds 10°
C./0.5 mm of length. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35)
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36. A method for fabricating a functionally-graded monolithic sintered working component for magnetic heat exchange, comprising:
-
providing a plurality of powders comprising elements in amounts sufficient for forming a La1-aRa(Fe1-x-yTyMx)13HzCb phase with a NaZn13 structure, wherein T is one or more of the elements selected from the group consisting of Mn, Co, Ni, Ti, V and Cr, M is one or more of the elements selected from the group consisting of Si and Al, and R is one or more of the elements selected from the group consisting of Ce, Nd, Y and Pr, wherein a is such that 0≤
a≤
0.5, b is such that 0≤
b≤
1.5, x is such that 0.05≤
x≤
0.2, y is such that 0≤
y≤
0.2, and z is such that 0≤
z≤
3;mixing the powders with a liquid and optionally with a binder and/or a dispersant to form a green body in the form of a slurry or paste in which an amount of at least one element selected from the group consisting of T, R, C and M varies in a pre-determined direction, heat treating the green body at a temperature T and for a time t selected to allow diffusion of one or more of the elements selected from the group consisting of T, R and C, and forming a working component from the green body comprising a Curie temperature that monotonically increases or monotonically decreases in the pre-determined direction, and wherein a gradient of the increase or decrease does not exceed 10°
C./0.5 mm anywhere in the working component.
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37. A method for fabricating a functionally-graded monolithic sintered working component for magnetic heat exchange, comprising:
-
providing a plurality of powders comprising elements in amounts sufficient for forming a La1-aRa(Fe1-x-yTyMx)13HzCb phase with a NaZn13 structure, wherein T is one or more of the elements selected from the group consisting of Mn, Co, Ni, Ti, V and Cr, M is one or more of the elements selected from the group consisting of Si and Al, and R is one or more of the elements selected from the group consisting of Ce, Nd, Y and Pr, wherein a is such that 0≤
a≤
0.5, b is such that 0≤
b≤
1.5, x is such that 0.05≤
x≤
0.2, y is such that 0≤
y≤
0.2, and z is such that 0≤
z≤
3;mixing the powders with a liquid and optionally with a binder and/or a dispersant to form a green body in the form of a slurry or paste in which an amount of at least one element selected form the group consisting of T, R, C and M varies in a pre-determined direction, the slurry or paste having a viscosity between 200 mPas and 100,000 mPas, heat treating the green body at a temperature T and for a time t selected to allow diffusion of one or more of the elements selected from the group consisting of T, R and C, forming a working component from the green body comprising a Curie temperature that monotonically increases or monotonically decreases in the pre-determined direction.
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38. A method for fabricating a functionally-graded monolithic sintered working component for magnetic heat exchange, comprising:
-
providing a plurality of powders comprising elements in amounts sufficient for forming a La1-aRa(Fe1-x-yTyMx)13HzCb phase with a NaZn13 structure, wherein T is one or more of the elements selected from the group consisting of Mn, Co, Ni, Ti, V and Cr, M is one or more of the elements selected from the group consisting of Si and Al, and R is one or more of the elements selected from the group consisting of Ce, Nd, Y and Pr, wherein a is such that 0≤
a≤
0.5, b is such that 0≤
b≤
1.5, x is such that 0.05≤
x≤
0.2, y is such that 0≤
y≤
0.2, and z is such that 0≤
z≤
3;mixing the powders with a liquid and optionally with a binder and/or a dispersant to form a green body in the form of a slurry or paste in which an amount of at least one element selected from the group consisting of T, R, C and M varies in a pre-determined direction, applying the slurry or paste to a surface layer by layer to form a stack such that the content of at least one element selected from the group consisting of R, T, C and M increases or decreases in a direction of the stack, heat treating the green body at a temperature T and for a time t selected to allow diffusion of one or more of the elements selected from the group consisting of T, R and C, forming a working component from the green body comprising a Curie temperature that monotonically increases or monotonically decreases in the pre-determined direction, and wherein a gradient of the increase or decrease does not exceed 10°
C./0.5 mm anywhere in the working component.
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39. A method for fabricating a functionally-graded monolithic sintered working component for magnetic heat exchange, comprising:
-
providing powder comprising elements in amounts sufficient for forming a La1-aRa(Fe1-x-yTyMx)13HzCb phase with a NaZn13 structure, wherein T is one or more of the elements selected from the group consisting of Mn, Co, Ni, Ti, V and Cr, M is one or more of the elements selected from the group consisting of Si and Al, and R is one or more of the elements selected from the group consisting of Ce, Nd, Y and Pr, wherein a is such that 0≤
a≤
0.5, b is such that 0≤
b≤
1.5, x is such that 0.05≤
x≤
0.2, y is such that 0≤
y≤
0.2, and z is such that 0≤
z≤
3;mixing the powders with a liquid and optionally with a binder and/or a dispersant to form a green body in the form of a slurry or paste in which an amount of at least one element selected from the group consisting of T, R, C and M varies in a pre-determined direction, applying the slurry or paste to a surface layer by layer to form a stack, each layer in the stack having a thickness of 10 μ
m to 60 μ
m,heat treating the green body at a temperature T and for a time t selected to allow diffusion of one or more of the elements selected from the group consisting of T, R and C, and forming a working component comprising a Curie temperature that monotonically increases or monotonically decreases in the pre-determined direction.
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Specification