Patent Application
20230290546
The present disclosure relates to permanent magnets and methods of making the same via additive manufacturing techniques.
Magnets pervade many technologies of modern life. Permanent magnets such as rare earth magnets (e.g., Nd-Fe-B) are widely used in electric machines and may be used in modem vehicles including electric vehicles and hybrid electric vehicles. For example, electric machines may include motors such as traction motors.
A permanent magnet is disclosed. The permanent magnet may include a magnetic phase and a buffer segment. The buffer segment may include a composition represented by the formula:
N may be nickel, aluminum or a combination thereof, M may be iron, cobalt or a combination thereof and Q may be chromium, titanium, molybdenum, copper, niobium or a combination thereof. In one variation, nickel may be present at greater than 25% by weight. In a refinement, N may be a combination of nickel and aluminum having an atomic ratio of 1:2 to 5:6, or more preferably 2:3 to 4:5, or even more preferably about 3:4. The atomic ratio of x:y may be from 0.3:1 to 1:2. Alternatively or additionally, the buffer segment may include a composition represented by the formula:
Iron may be greater than 5% by weight, and the atomic ratio of a:b may be from 0.3:1 and 1:3.
A method of making a magnet is also disclosed. The method may include additively manufacturing a first and second layer disposed upon one another. The first and second layer may be formed from first and second powder mixtures. The first powder mixture may include a magnetic alloy and/or a buffer alloy. The second mixture may include the other of the magnetic alloy or the buffer alloy. The buffer alloy may form a buffer layer or segment having a composition represented by the formula:
N may be nickel, aluminum or a combination thereof, M may be iron, cobalt or a combination thereof and Q may be chromium, titanium, molybdenum, copper, niobium or a combination thereof. In one variation, nickel may be present at greater than 25% by weight. In a refinement, N may be a combination of nickel and aluminum having an atomic ratio of 1:2 to 5:6, or more preferably 2:3 to 4:5, or even more preferably about 3:4. The atomic ratio of x:y may be from 0.3:1 to 1:2. Alternatively or additionally, the buffer layer or segment may include a composition represented by the formula:
Iron may be greater than 5% by weight, and the atomic ratio of a:b may be from 0.3:1 and 1:3.
A magnetic having a plurality of stratified magnetic segments and a plurality of stratified buffer segments is disclosed. The buffer segments may include a composition represented by the formula:
N may be nickel, aluminum or a combination thereof, M may be iron, cobalt or a combination thereof and Q may be chromium, titanium, molybdenum, copper, niobium or a combination thereof. In a variation, nickel may be present at greater than 25% by weight. In a refinement, N may be a combination of nickel and aluminum having an atomic ratio of 1:2 to 5:6, or more preferably 2:3 to 4:5, or even more preferably about 3:4. The atomic ratio of x:y may be from 0.3:1 to 1:2. Alternatively or additionally, the buffer layer or segment may include a composition represented by the formula:
Iron may be greater than 5% by weight, and the atomic ratio of a:b may be from 0.3:1 and 1:3.
Embodiments of the present disclosure are described herein. It is to be understood, however, that the disclosed embodiments are merely examples and other embodiments can take various and alternative forms. The figures are not necessarily to scale. Some features could be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the embodiments of the present invention. As those of ordinary skill in the art will understand, various features illustrated and described with reference to any one of the figures can be combined with features illustrated in one or more other figures to produce embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. Various combinations and modifications of the features consistent with the teachings of this disclosure, however, could be desired for particular applications or implementations.
Unless expressly stated to the contrary, percent, “parts of,” and ratio values are by weight. The first definition of an acronym or other abbreviation applies to all subsequent uses herein of the same abbreviation and applies mutatis mutandis to normal grammatical variations of the initially defined abbreviation. Unless expressly stated to the contrary, measurement of a property is determined by the same technique as previously or later referenced for the same property.
This disclosure is not limited to the specific embodiments and methods described below, as specific components and/or conditions may vary. Furthermore, the terminology used herein is used only for the purpose of describing particular embodiments and is not intended to be limiting in any way.
As used in the specification and the appended claims, the singular form “a,” “an,” and “the” comprise plural referents unless the context clearly indicates otherwise. For example, reference to a component in the singular is intended to comprise a plurality of components.
The term “substantially” or “generally” may be used herein to describe disclosed or claimed embodiments. The term “substantially” may modify a value or relative characteristic disclosed or claimed in the present disclosure. In such instances, “substantially” may signify that the value or relative characteristic it modifies is within ± 0%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5% or 10% of the value or relative characteristic.
It should also be appreciated that integer ranges explicitly include all intervening integers. For example, the integer range 1-10 explicitly includes 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10. Similarly, the range 1 to 100 includes 1, 2, 3, 4 ... 97, 98, 99, 100. Similarly, when any range is called for, intervening numbers that are increments of the difference between the upper limit and the lower limit divided by 10 can be taken as alternative upper or lower limits. For example, if the range is 1.1. to 2.1 the following numbers 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, and 2.0 can be selected as lower or upper limits.
As shown in
The magnetic phase or segments 200 may be any alloy having magnetic properties. In some variations, a rare earth magnet or alloy such as Nd-Fe-B may be used. The buffer segments 300 may be metals, alloys and compounds that enhance performance, provide superior performance, or alleviate undesirable properties.
In one variation, a buffer segment and/or layer may include an alloy such as with iron (Fe), cobalt (Co), nickel (Ni) or a combination thereof. The alloy may also include chromium (Cr), titanium (Ti), aluminum (Al), molybdenum (Mo), copper (Cu), niobium (Nb) or a combination thereof. For example, the buffer segment 200 may include a composition represented by the following formula:
In one or more embodiments, N is nickel, aluminum or a combination thereof, M is iron, cobalt, or a combination thereof, and Q is chromium, titanium, molybdenum, or a combination thereof. In a refinement, Q may also include copper, niobium, or combinations thereof. In another refinement, the atomic ratio of x:y is from 0.3:1 to 1:3, or more preferably from 0.5:1 to 1:2, or even more preferably from 0.8:1.2. For example, the atomic ratio of x:y may be 1:1. In yet another refinement, nickel may be present at greater than 15% by weight, or more preferably greater than 20% by weight or even more preferably greater than 25% by weight of the composition. In a refinement, N may be a combination of nickel and aluminum having an atomic ratio of 1:2 to 5:6, or more preferably 2:3 to 4:5, or even more preferably about 3:4.
In another variation, a buffer segment and/or layer may include a composition represented the following formula:
In one or more embodiments, Q is copper, cobalt, aluminum, titanium, niobium, or a combination thereof. In a refinement, nickel may be present at greater than 30% by weight, or more preferably greater than 35% by weight, or even more preferably greater than 40% by weight of the composition. In still another refinement, iron (Fe) may be present at 10 to 40% by weight, or more preferably 15 to 35% by weight, or even more preferably 20 to 30% by weight of the composition.
In yet another variation, a buffer layer and/or segment may include a composition represented by the formula:
In a refinement, chromium may be present at 10-45% by weight, or more preferably 15-40%, or even more preferably 20-35% by weight of the composition. In yet another refinement, cobalt may be present 1-35% by weight, or more preferably 3-30%, or even more preferably 5-25% by weight of the composition. In yet another refinement, iron makes up the remaining portion.
In still another variation, a buffer layer and/or composition may include a composition represented by the following formula:
In a refinement, vanadium is present at greater than 5% by weight, or more preferably greater than 10%, or even more preferably greater 15% by weight of the composition with the remaining portion being the combination of iron and cobalt. In still another refinement, the atomic ratio of x:y (i.e., iron:cobalt) is from 0.3:1 to 1:3, or more preferably from 0.5:1 to 1:2, or even more preferably from 0.8:1.2. For example, the atomic ratio of x:y may be 1:1.
In still another embodiment, the one or more buffer segments 300 may be disposed within the magnetic phase 200 or within a magnetic layer itself as discrete portions such as buffer particles 308, as shown in
The combination of magnetic segments and buffer segments is not particularly limited but may include alternating layers, or hatch patterns. If alternating layers are used, they may be substantially horizontal, vertical and/or diagonal. For example, as shown in
A method of making a magnet is also disclosed. The method 400 includes additively manufacturing a first segment or layer (i.e., step 402), and a second segment or layer (i.e., step 404) first powder mixture including a magnetic alloy or a second powder mixture including a first buffer alloy. In a variation, the second layer may be disposed on the first layer. The first layer may be made from, for example, laser melting a first powder mixture and the second layer may be made from, for example, laser melting a second powder mixture. The first powder mixture may include a magnetic alloy or a buffer alloy. The second powder mixture may include the other of the magnetic alloy or the buffer alloy. This process may be repeated to additional magnetic or buffer layers or segments (i.e., step 406). If more than one buffer layers or segments are included, they may be made from the same or different buffer alloys. The buffer alloy may form one or more of the buffer layers as disclosed herein.
A layer or segment may include both a discrete magnetic phase and a discrete buffer phase such as by mixing the magnetic alloy powder and buffer alloy powder, as shown in
While exemplary embodiments are described above, it is not intended that these embodiments describe all possible forms encompassed by the claims. The words used in the specification are words of description rather than limitation, and it is understood that various changes can be made without departing from the spirit and scope of the disclosure. As previously described, the features of various embodiments can be combined to form further embodiments of the invention that may not be explicitly described or illustrated. While various embodiments could have been described as providing advantages or being preferred over other embodiments or prior art implementations with respect to one or more desired characteristics, those of ordinary skill in the art recognize that one or more features or characteristics can be compromised to achieve desired overall system attributes, which depend on the specific application and implementation. These attributes can include, but are not limited to strength, durability, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. As such, embodiments described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and can be desirable for particular applications.
