阅读说明：本技术 混合预烧结的预成型件、生坯预成型件以及方法 (Hybrid pre-sintered preform, green body preform and method ) 是由 崔燕 斯里坎特·钱德拉杜·科蒂林加姆 布赖恩·李·托利森 布莱恩·莱斯利·亨德森 于 2018-08-02 设计创作，主要内容包括：本公开提供了一种方法,该方法包括将芯合金的至少一个芯与钎焊粘结剂一起搅拌以形成包括涂覆有钎焊粘结剂的第一层的至少一个芯的至少一个涂覆的芯。该方法还包括将至少一个涂覆的芯与包括第一合金的第一金属粉末和第二合金的第二金属粉末的粉末组合物一起搅拌以形成具有第一合金和第二合金的第一粉末组合物层的生坯预成型件。该方法还包括烧结生坯预成型件以形成至少一个混合预烧结的预成型件。生坯预成型件包括芯；钎焊粘结剂的第一层,该第一层涂覆在芯上；以及粉末组合物,该粉末组合物涂覆在第一层上。混合预烧结的预成型件包括芯；以及第一层,该第一层被烧结到芯。(The present disclosure provides a method comprising stirring at least one core of a core alloy with a brazing binder to form at least one coated core comprising at least one core coated with a first layer of the brazing binder. The method also includes stirring the at least one coated core with a powder composition including a first metal powder of the first alloy and a second metal powder of the second alloy to form a green preform having a layer of the first powder composition of the first alloy and the second alloy. The method also includes sintering the green preform to form at least one hybrid pre-sintered preform. The green preform comprises a core; a first layer of braze binder coated on the core; and a powder composition coated on the first layer. The hybrid pre-sintered preform comprises a core; and a first layer sintered to the core.)

1. A method, comprising:

agitating at least one core of a core alloy with a brazing binder to form at least one coated core comprising the at least one core coated with a first layer of the brazing binder;

stirring the at least one coated core with a powder composition comprising a first metal powder of a first alloy and a second metal powder of a second alloy to form a green preform having a layer of the first powder composition of the first alloy and the second alloy; and

sintering the green body preform to form at least one hybrid pre-sintered preform (PSP).

2. The method of claim 1, wherein the first alloy has a first melting point of at least about 2400 ° f and the second alloy has a second melting point below about 2350 ° f.

3. The method of claim 1, wherein the braze binder is a braze binder gel.

4. The method of claim 1, further comprising stirring the green preform with the braze binder to form a braze binder coated green preform, and stirring the braze binder coated green preform with the first metal powder and the second metal powder to form a powder coated green preform, wherein the sintering is performed on the powder coated green preform.

5. The method of claim 1, wherein the at least one core is spherical.

6. The method of claim 1, wherein the core alloy comprises a composition, by weight, of between about 8% and about 10% molybdenum, between about 20.5% and about 23% chromium, between about 17% and about 20% iron, between about 0.2% and about 1% tungsten, between about 0.5% and about 2.5% cobalt, between about 0.05% and about 0.15% carbon, up to about 1% silicon, up to about 1% manganese, up to about 0.01% boron, up to about 0.04% phosphorus, up to about 0.03% sulfur, incidental impurities, and the balance nickel.

7. The method of claim 1, wherein the first alloy comprises a composition, by weight, between about 9.3% and about 9.7% tungsten, between about 9.0% and about 9.5% cobalt, between about 8.0% and about 8.5% chromium, between about 5.4% and about 5.7% aluminum, about 3.2% tantalum, about 1.4% hafnium, up to about 0.25% silicon, up to about 0.1% manganese, between about 0.06% and about 0.09% carbon, incidental impurities, and the balance nickel.

8. The method of claim 1, wherein the second alloy comprises a composition, by weight, of about 14% chromium, about 10% cobalt, about 3.5% aluminum, about 2.5% tantalum, about 2.75% boron, about 0.05% yttrium, incidental impurities, and the balance nickel.

9. The method of claim 1, wherein the first metal powder and the second metal powder are present in the powder composition in a ratio in a range of 90:10 to 45:55 by weight.

10. The method of claim 1, further comprising brazing one of the at least one hybrid PSP in a passage to seal the passage.

11. The method of claim 10, wherein the passage is a bucket ball slot of a gas turbine bucket.

12. The method of claim 1, wherein the agitating at least one core of a core alloy with a brazing binder is performed in a plastic container with the at least one core and the brazing binder.

13. The method of claim 1, wherein the agitating at least one core of a core alloy with a brazing binder and the agitating the at least one coated core with a powder composition consisting of a first metal powder of a first alloy and a second metal powder of a second alloy is performed by a three-dimensional shaking mixer.

14. A green body preform comprising:

a core of a core alloy;

a first layer of brazing adhesive coated on the core; and

a powder composition comprising a first metal powder of a first alloy and a second metal powder of a second alloy, the powder composition coated on the first layer, the first alloy having a first melting point of at least about 2400 ° F, and the second alloy having a second melting point below about 2350 ° F.

15. The green body preform of claim 14, further comprising:

a second layer of the braze binder coated on the powder composition of the first metal powder and the second metal powder; and

a powder composition of the first metal powder of the first alloy and the second metal powder of the second alloy, the powder composition coated on the second layer.

16. A hybrid pre-sintered preform (PSP) comprising:

a core of a core alloy; and

a first layer sintered to the core, the first layer being a sintered powder composition including a first alloy from a first metal powder and a second alloy from a second metal powder, the first alloy having a first melting point of at least about 2400 DEG F, and the second alloy having a second melting point below about 2350 DEG F.

17. The hybrid PSP of claim 16, further comprising a second layer sintered to the first layer, the second layer having the sintered powder composition of the first alloy and the second alloy.

18. The hybrid PSP of claim 16, wherein the core is spherical.

19. The hybrid PSP of claim 16, wherein:

the core alloy comprises a composition, by weight, of between about 8% and about 10% molybdenum, between about 20.5% and about 23% chromium, between about 17% and about 20% iron, between about 0.2% and about 1% tungsten, between about 0.5% and about 2.5% cobalt, between about 0.05% and about 0.15% carbon, up to about 1% silicon, up to about 1% manganese, up to about 0.01% boron, up to about 0.04% phosphorus, up to about 0.03% sulfur, incidental impurities, and the balance nickel;

the first alloy comprises a composition, by weight, of between about 9.3% and about 9.7% tungsten, between about 9.0% and about 9.5% cobalt, between about 8.0% and about 8.5% chromium, between about 5.4% and about 5.7% aluminum, about 3.2% tantalum, about 1.4% hafnium, up to about 0.25% silicon, up to about 0.1% manganese, between about 0.06% and about 0.09% carbon, incidental impurities, and the balance nickel; and is

The second alloy includes a composition, by weight, of about 14% chromium, about 10% cobalt, about 3.5% aluminum, about 2.5% tantalum, about 2.75% boron, about 0.05% yttrium, incidental impurities, and the balance nickel.

20. The hybrid PSP of claim 16, wherein the first alloy and the second alloy are present in the sintered powder composition in a ratio in a range of 90:10 to 45:55 by weight.

Technical Field

Embodiments of the present invention relate to green body preforms, pre-sintered preforms, and methods of forming and using pre-sintered preforms. More particularly, embodiments of the present invention relate to hybrid green preforms having a core of a first alloy and a powder composition on the core, hybrid pre-sintered preforms having a core of a first alloy and a pre-sintered preform on a surface of the core, and methods of forming and using such preforms.

Background

Brazing is a useful method of joining two components or materials together. However, the brazing method may depend on specialized materials, such as brazing paste. The solder paste itself may have a short shelf life and it may be difficult to control e.g. the consistency, amount and location of the solder paste, especially if access of the solder paste to the soldering location is limited. If a very small amount of solder paste is applied, the part may need to be reworked. If too much solder paste is applied, the solder paste may flow to undesired areas of the part. In addition, the use of solder paste may cause inconsistencies in the soldering process, thereby causing uneven parts to be manufactured or repaired.

More specifically, turbine components are often manufactured with openings or passages that, in some cases, are no longer needed or advantageously sealed or blocked after manufacture. Examples in gas turbine systems include a tip plug, a gas charge hole, and a ball slot. These openings may be difficult to access for sealing or blocking. Conventionally, such openings are sealed or blocked by brazing pre-sintered preform balls or metal balls of a superalloy (such as Hastelloy X) with a brazing paste. The number of suppliers of pre-sintered preforms is limited and obtaining pre-sintered preforms from suppliers, especially customized pre-sintered preforms, can be time consuming and costly.

Disclosure of Invention

In one embodiment, a method includes stirring at least one core of a core alloy with a braze binder to form at least one coated core including at least one core coated with a first layer of braze binder. The method also includes stirring the at least one coated core with a powder composition including a first metal powder of the first alloy and a second metal powder of the second alloy to form a green preform having a layer of the first powder composition of the first alloy and the second alloy. The method also includes sintering the green preform to form at least one hybrid pre-sintered preform.

In another embodiment, a green body preform comprises: a core of a core alloy; a first layer of braze binder coated on the core; and a powder composition comprising a first metal powder of a first alloy and a second metal powder of a second alloy, the powder composition coated on the first layer. The first alloy has a first melting point of at least about 2400 ° f, and the second alloy has a second melting point below about 2350 ° f.

In yet another embodiment, a hybrid pre-sintered preform comprises: a core of a core alloy; and a first layer sintered to the core. The first layer is a sintered powder composition including a first alloy from a first metal powder and a second alloy from a second metal powder. The first alloy has a first melting point of at least about 2400 ° f, and the second alloy has a second melting point below about 2350 ° f.

Other features and advantages of the present invention will be apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

Drawings

Fig. 1 schematically illustrates a method of forming a hybrid pre-sintered preform.

Fig. 2 schematically illustrates a method of brazing a hybrid pre-sintered preform.

Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

Detailed Description

Provided herein are hybrid green preforms having a core of a first alloy and a powder composition on the core, hybrid pre-sintered preforms (PSPs) having a core of a first alloy and a pre-sintered preform on a surface of the core, and methods of forming and using such preforms.

For example, embodiments of the present disclosure provide a hybrid PSP, provide a hybrid PSP ball, provide a significantly lower cost hybrid PSP ball, provide easier control over the production of a hybrid PSP ball, allow for the production of a hybrid PSP in a plant, allow for the production of a hybrid PSP ball in a plant, provide a hybrid PSP ball for closing a turbine bucket ball groove, provide a hybrid PSP ball for sealing a tip plug, provide a hybrid PSP ball for blocking an inflation hole, or a combination thereof, as compared to concepts failing to include one or more of the features disclosed herein.

As used herein, "B93" is meant to include between about 13.7% and about 14.3% chromium (Cr), between about 9.0% and about 10.0% cobalt (Co), between 4.6% and about 5.0% titanium (Ti), between about 4.5% and about 4.8% silicon (Si), between about 3.7% and about 4.3% molybdenum (Mo), between about 3.7% and about 4.3% by weightAn alloy of a composition of between about 3.7% and about 4.0% tungsten (W), between about 2.8% and about 3.2% aluminum (Al), between about 0.50% and about 0.80% boron (B), between about 0.13% and about 0.19% carbon (C), incidental impurities, and the balance nickel (Ni). B93 is a compound obtainable for example from the company eurekancomei of philphne california switzerland (Oerlikon Metco,

switzerland) commercially available.

As used herein, "BNi-2" refers to an alloy of a composition comprising by weight about 7% Cr, about 4.5% Si, about 3% B, about 3% iron (Fe), incidental impurities, and the balance Ni. BNi-2 is commercially available from, for example, Lucas-Milhaupt, Inc., Cudahy, Wis, Calif.

As used herein, "BNi-3" refers to an alloy comprising a composition of about 4.5% Si, about 3% B, incidental impurities, and the balance Ni, by weight. BNi-3 is commercially available, for example, from Lucos Mihart, Inc.

As used herein, "BNi-5" refers to an alloy comprising a composition of about 19% Cr, about 10% Si, incidental impurities, and the balance Ni, by weight. BNi-5 is commercially available, for example, from Lucos Mihart, Inc.

As used herein, "BNi-6" refers to an alloy of the composition comprising about 11% by weight of phosphorus (P), incidental impurities, and the balance Ni. BNi-6 is commercially available, for example, from Lucos Mihart, Inc.

As used herein, "BNi-7" refers to an alloy comprising a composition of about 14% Cr, about 10% P, incidental impurities, and the balance Ni, by weight. BNi-7 is commercially available, for example, from Lucos Mihart, Inc.

As used herein, "BNi-9" refers to an alloy comprising a composition of about 15% Cr, about 3% B, incidental impurities, and the balance Ni, by weight. BNi-9 is commercially available, for example, from Lucos Mihart, Inc.

As used herein, "BNi-10" refers to an alloy of composition comprising by weight about 16% W, about 11.5% Cr, about 3.5% Si, about 3.5% Fe, about 2.5% B, about 0.5% C, incidental impurities, and the balance Ni. BNi-10 is commercially available from, for example, hua China incorporated Welding manufacturing ltd (Huazhong Welding manufacturing co., ltd., Hefei, China).

As used herein, "BRB" refers to an alloy of a composition including, by weight, between about 13.0% and about 14.0% Cr, between about 9.0% and about 10.0% Co, between about 3.5% and about 3.8% Al, between about 2.25% and about 2.75% B, incidental impurities, and the balance Ni. BRB is commercially available from, for example, eurekancecox.

As used herein, "D15" refers to an alloy of a composition that includes, by weight, between about 14.8% and about 15.8% Cr, between about 9.5% and about 11.0% Co, between about 3.2% and about 3.7% Al, between about 3.0% and about 3.8% tantalum (Ta), between about 2.1% and about 2.5% B, incidental impurities, and the balance Ni. D15 is commercially available from, for example, eurekancomei.

As used herein, "DF 4B" refers to an alloy comprising a composition, by weight, of between about 13.0% and about 15% Cr, between about 9.0% and about 11.0% Co, between about 3.25% and about 3.75% Al, between about 2.25% and about 2.75% Ta, between about 2.5% and about 3.0% B, between about 0.01% and about 0.10% yttrium (Y), incidental impurities, and the balance Ni. DF4B is commercially available from, for example, eurekancomei.

As used herein, "GTD 111" refers to an alloy of impurities including, by weight, between about 13.70% and about 14.30% Cr, between about 9.0% and about 10.0% Co, between about 4.7% and about 5.1% Ti, between about 3.5% and about 4.1% W, between about 2.8% and about 3.2% Al, between about 2.4% and about 3.1% Ta, between about 1.4% and about 1.7% Mo, about 0.35% Fe, about 0.3% Si, about 0.15% niobium (Nb), between about 0.08% and about 0.12% C, about 0.1% manganese (Mn), about 0.1% copper (Cu), about 0.04% zirconium (Zr), between about 0.005% and about 0.005% B, about 0.020% P, about 0.015% P, and about 005% Ni, the balance of incidental impurities S.

As used herein, "GTD 444" refers to an alloy of composition including, by weight, about 9.75% Cr, about 7.5% Co, about 4.2% Al, about 3.5% Ti, about 4.8% Ta, about 6% W, about 1.5% Mo, up to about 0.5% Nb, up to about 0.2% Fe, up to about 0.2% Si, up to about 0.15% hafnium (Hf), up to about 0.08% C, up to about 0.009% Zr, up to about 0.009% B, incidental impurities, and the balance Ni.

As used herein, "Hastelloy X" refers to an alloy comprising a composition of between about 8% and about 10% Mo, between about 20.5% and about 23% Cr, between about 17% and about 20% Fe, between about 0.2% and about 1% W, between about 0.5% and about 2.5% Co, between about 0.05% and about 0.15% C, up to about 1% Si, up to about 1% Mn, up to about 0.01% B, up to about 0.04% P, up to about 0.03% S, incidental impurities, and the balance Ni, by weight.

As used herein, "HAYNES 188" refers to an alloy of a composition comprising, by weight, between about 21% and about 23% Cr, between about 20% and about 24% Ni, between about 13% and about 15% W, up to about 3% Fe, up to about 1.25% Mn, between about 0.2% and about 0.5% Si, between about 0.05% and about 0.15% C, between about 0.03% and about 0.12% lanthanum (La), up to about 0.02% P, up to about 0.015% B, up to about 0.015% S, incidental impurities, and the balance Co.

As used herein, "HAYNES 230" refers to an alloy of a composition comprising, by weight, about 22% Cr, about 2% Mo, about 0.5% Mn, about 0.4% Si, about 14% W, about 0.3% Al, about 0.1% C, about 0.02% La, incidental impurities, and the balance Ni.

As used herein, "INCONEL 738" refers to an alloy that includes a balance of impurities of between about 15.7% and about 16.3% Cr, between about 8.0% and about 9.0% Co, between about 3.2% and about 3.7% Ti, between about 3.2% and about 3.7% Al, between about 2.4% and about 2.8% W, between about 1.5% and about 2.0% Ta, between about 1.5% and about 2.0% Mo, between about 0.6% and about 1.1% Nb, up to about 0.5% Fe, up to about 0.3% Si, up to about 0.2% Mn, between about 0.15% and about 0.20% C, between about 0.05% and about 0.15% Zr, up to about 0.015% S, between about 0.005% and about 0.015% Ni, and the balance by weight of the alloy.

As used herein, "L605" refers to an alloy of a composition comprising, by weight, between about 19% and about 21% Cr, between about 14% and about 16% W, between about 9% and about 11% Ni, up to about 3% Fe, between about 1% and about 2% Mn, between about 0.05% and about 0.15% C, up to about 0.4% Si, up to about 0.04% P, up to about 0.03% S, incidental impurities, and the balance Co.

As used herein, "MarM 247" refers to an alloy of a composition comprising, by weight, between about 9.3% and about 9.7% W, between about 9.0% and about 9.5% Co, between about 8.0% and about 8.5% Cr, between about 5.4% and about 5.7% Al, optionally about 3.2% Ta, optionally about 1.4% Hf, up to about 0.25% Si, up to about 0.1% Mn, between about 0.06% and about 0.09% C, incidental impurities, and the balance Ni.

As used herein, "MarM 509" refers to an alloy that includes a composition of between about 22.5% and about 24.25% Cr, between about 9% and about 11% Ni, between about 6.5% and about 7.5% W, between about 3% and about 4% Ta, up to about 0.3% Ti (e.g., between about 0.15% and about 0.3% Ti), up to about 0.65% C (e.g., between about 0.55% and about 0.65% C), up to about 0.55% Zr (e.g., between about 0.45% and about 0.55% Zr), incidental impurities, and the balance Co, by weight.

As used herein, "MarM 509B" refers to an alloy of a composition comprising, by weight, between about 22.00% and about 24.75% Cr, between about 9.0% and about 11.0% Ni, between about 6.5% and about 7.6% W, between about 3.0% and about 4.0% Ta, between about 2.6% and about 3.16% B, between about 0.55% and about 0.64% C, between about 0.30% and about 0.60% Zr, between about 0.15% and about 0.30% Ti, up to about 1.30% Fe, up to about 0.40% Si, up to about 0.10% Mn, up to about 0.02% S, incidental impurities, and the balance Co. MM509B is commercially available from, for example, WESGO Ceramics (WESGO Ceramics).

As used herein, "Ren e 108" is meant to include, by weight, between about 9% and about 10% Co, between about 9.3% and about 9.7% W, between about 8.0% and about 8.7% Cr, between about 5.25% and about 5.75% Al, between about 2.8% and about 3.3% Ta, between about 1.3% and about 1.7% Hf, up to about 0.9% Ti (e.g., between about 0.6% and about 0.9% Ti), up to about 0.6% Mo (e.g., between about 0.4% and about 0.6% Mo), up to about 0.2% Fe, up to about 0.12% Si, up to about 0.1% Mn, up to about 0.1% Cu, up to about 0.1% C (e.g., between about 0.07% and about 0.1% C), up to about 0.02% Nb (e.g., between about 0.02% B), up to about 0.02% Nb (e.02% B), between about 0.02% B, between about 0.1% and about 0.02%, (e., An alloy of a composition of up to about 0.01% P, up to about 0.004% S, incidental impurities, and the balance Ni.

As used herein, "Ren 142" refers to an alloy that includes a composition of, by weight, about 12% Co, about 6.8% Cr, about 6.4% Ta, about 6.1% Al, about 4.9% W, about 2.8% rhenium (Re), about 1.5% Mo, about 1.5% Hf, about 0.12% C, about 0.02% Zr, about 0.015% B, incidental impurities, and the balance Ni.

As used herein, "Ren 195" refers to an alloy of a composition including, by weight, about 7.6% Cr, about 3.1% Co, about 7.8% Al, about 5.5% Ta, about 0.1% Mo, about 3.9% W, about 1.7% Re, about 0.15% Hf, incidental impurities, and the balance Ni.

As used herein, "Ren N2" refers to an alloy of composition including, by weight, about 13% Cr, about 7.5% Co, about 6.6% Al, about 5% Ta, about 3.8% W, about 1.6% Re, about 0.15% Hf, incidental impurities, and the balance Ni.

As used herein, "T800" refers to an alloy of a composition comprising, by weight, between about 27.0% and about 30.0% Mo, between about 16.5% and about 18.5% Cr, between about 3.0% and 3.8% Si, up to about 1.5% Fe, up to about 1.5% Ni, up to about 0.15% oxygen (O), up to about 0.08% C, up to about 0.03% P, up to about 0.03% S, incidental impurities, and the balance Co. T800 is manufactured, for example, by deloso StelliteInc, and is commercially available, for example, from WESGO ceramics.

Referring to FIG. 1, the method includes placing a core 10 of a core alloy in a vessel 12 with a braze binder 14. The core 10 in fig. 1 is spherical. The container 12 in fig. 1 is a capped plastic bottle. The vessel 12 is placed in a mixer 20 that shakes the vessel 12 to agitate the cores 10 and braze adhesive 14 to form coated cores 22 of the cores 10, each coated with a layer of braze adhesive 14.

Still referring to fig. 1, a first powder 30 of a first alloy is mixed with a second powder 32 of a second alloy to form a powder composition 34. The first alloy and the second alloy have different melting temperatures. The powder composition 34 and coated core 22 are placed in the container 12. The container 12 for the coated core 22 and the powder composition 34 in fig. 1 is a capped plastic bottle similar to or the same as the container 12 for the core 10 and the braze binder 14, but preferably not the same container 12. The vessel 12 is placed in a mixer 20 that shakes the vessel 12 to stir the coated core 22 and the powder composition 34 to form green preforms 40 of the core 10, each coated with a layer of braze binder 14 and the powder composition 34 adhered to the layer of braze binder 14 in an unsintered state. The same mixer 20 or different mixers 20 may be used for both stirrers.

Still referring to fig. 1, the alternating steps of applying the brazing binder 14 layer and applying the powder composition 34 may be repeated any number of times until a sufficient amount of the powder composition 34 has been applied to the core 10 to form the powder coated green preform 50. In fig. 1, the powder coated green preform 50 has two layers of braze binder 14 and two layers of powder composition 34, but the powder coated green preform 50 may alternatively be identical to the green preform 40 or may have additional powder composition 34 from additional layers. The powder coated green preform 50 is then sintered in a sintering furnace 52 to form a hybrid pre-sintered preform 60 of the core 10, which is coated with a sintered powder composition 62. In some embodiments, the sintering furnace 52 is a vacuum furnace. In some embodiments, the sintering is performed in a vacuum furnace. In some embodiments, the temperature used for sintering is in the range of about 1150 ℃ (about 2100 ° f) to about 1290 ℃ (about 2350 ° f). The braze binder 14 is burned off during sintering.

In some embodiments, the hybrid pre-sintered preform 60 is ready for brazing directly after sintering without any additional processing steps. In other embodiments, the hybrid pre-sintered preform 60 may be ground after sintering but prior to brazing or use in production to alter surface texture or geometry. In some embodiments, the grinding produces a smooth surface geometry on the outer surface of the hybrid pre-sintered preform 60. In some embodiments, the grinding may alternatively or additionally produce a rounded geometry on the outer surface of the hybrid pre-sintered preform 60.

Referring to fig. 2, the method includes placing a hybrid pre-sintered preform 60 in the passage 80 of the component 70, the hybrid pre-sintered preform including the core 10 and the sintered powder composition 62 surrounding the core 10. The hybrid pre-sintered preform 60 is then brazed to the component 70 in the passage 80 of the component. In some embodiments, the temperature used for brazing is in the range of about 1150 ℃ (about 2100 ° f) to about 1290 ℃ (about 2350 ° f). In some embodiments, the time for brazing is in the range of about 10 minutes to about 30 minutes. The core 10, braze joint 90, component 70, and passage 80 are all visible in the final image of fig. 2, where the diameter of the core 10 is about 5.7mm (about 0.23 inch).

The core 10 may have a maximum length dimension (in the case of a spherical geometry, i.e. a diameter) within the following range: about 2.5mm (about 0.1 inch) to about 19.1mm (about 0.75 inch), alternatively about 12.7mm (about 0.5 inch) to about 19.1mm (about 0.75 inch), alternatively about 2.5mm (about 0.1 inch) to about 12.7mm (about 0.5 inch), alternatively about 3.8mm (about 0.15 inch) to about 10.2mm (about 0.4 inch), alternatively about 5.1mm (about 0.2 inch) to about 7.6mm (about 0.3 inch), alternatively about 5.1mm (about 0.2 inch) to about 6.4mm (about 0.25 inch), or any value, range, or subrange therebetween.

In some embodiments, the core alloy of the core 10 is a superalloy. The core alloy may include one or more refractory alloys, superalloys, nickel-based superalloys, cobalt-based superalloys, iron-based superalloys, titanium-aluminum superalloys, iron-based alloys, steel alloys, stainless steel alloys, cobalt-based alloys, nickel-based alloys, titanium-based alloys, Hastelloy X, HAYNES188, HAYNES 230, or combinations thereof. In some embodiments, the core alloy is not a pre-sintered preform.

The brazing binder 14 may have any binder composition that forms a coating on the core 10, holds the powder composition 34 on the core 10 prior to brazing, and burns off during the brazing step. The braze binder 14 preferably includes a binder component in a solvent. In some embodiments, the braze binder 14 has the consistency of a gel. In some embodiments, the brazing adhesive 14 is an adhesive gel. In some embodiments, the binder gel is a conventional binder gel. In some embodiments, the brazing binder does not include any brazing metal or alloy.

In some embodiments, the powder composition 34 includes a first alloy and a second alloy that are miscible with each other as distinct phases. The first alloy has a higher melting temperature than the second alloy. The first alloy is a high melting point alloy powder and may include a first melting point of at least about 1320 ℃ (about 2400 ° f), and the second alloy is a low melting point alloy powder and may include a second melting point below about 1290 ℃ (about 2350 ° f).

The first alloy may include one or more refractory alloys, superalloys, nickel-based superalloys, cobalt-based superalloys, iron-based superalloys, titanium-aluminum superalloys, iron-based alloys, steel alloys, stainless steel alloys, cobalt-based alloys, nickel-based alloys, titanium-based alloys, T800, GTD 111, GTD 444, HAYNES188, HAYNES 230, INCONEL 738, L605, MarM247, MarM509, Ren 108, Ren 142, Ren 195, Ren N2, or combinations thereof.

The second alloy may include one or more braze alloys, iron-based alloys, steel alloys, stainless steel alloys, cobalt-based alloys, nickel-based alloys, titanium-based alloys, DF4B, D15, MarM509B, B93, BNi-2, BNi-3, BNi-5, BNi-6, BNi-7, BNi-9, BNi-10, BRB, or combinations thereof.

In some embodiments, powder composition 34 further comprises one or more ceramic additives such as, but not limited to, alumina, silicon carbide, tungsten carbide, titanium nitride, titanium carbonitride, titanium carbide, or combinations thereof.

In some embodiments, the powder composition 34 includes a mixture of the first alloy and the second alloy in the following amounts: about 90% by weight of the first alloy and about 10% by weight of the second alloy, alternatively about 80% by weight of the first alloy and about 20% by weight of the second alloy, alternatively about 70% by weight of the first alloy and about 30% by weight of the second alloy, alternatively about 60% by weight of the first alloy and about 40% by weight of the second alloy, alternatively about 50% by weight of the first alloy and about 50% by weight of the second alloy, alternatively about 45% by weight of the first alloy and about 55% by weight of the second alloy, or any value, range, or subrange therebetween. In some embodiments, the first alloy is MarM 247. In some embodiments, the second alloy is DF 4B.

In some embodiments, every other brazing binder 14 layer of each brazing binder 14 layer has the same composition. In some embodiments, every other powder composition 34 coating has the same composition. In some embodiments, the composition of at least one of the powder composition 34 coatings is different from the composition of at least one other of the powder composition 34 coatings. In some embodiments, the first alloy or the second alloy is different in at least one of the coatings. In some embodiments, the first alloy is the same in all coatings and the second alloy is the same in all coatings, but the relative amounts of the first alloy and the second alloy are varied. In some embodiments, the coating provides a gradient in the relative amounts of the first alloy and the second alloy in the coating from the innermost coating to the outermost coating. In some embodiments, the ratio of the first alloy to the second alloy decreases from the innermost coating to the outermost coating.

Although the core 10 is shown as spherical in the figures, the core 10 may have any geometric shape that facilitates placement in a via and sealing of an opening, including but not limited to spherical, ovoid, cylindrical, conical, cubic, rectangular, or conical.

The container 12 may be of any size and shape and may be made of any material capable of holding the core 10 and the braze binder 14 or powder composition 34 during the agitating step such that a uniform or substantially uniform coating of braze binder 14 or powder composition 34 is applied to the outer surface of the core 10.

The proportion and amount of braze binder 14 relative to the core 10 is preferably selected to provide a uniform or substantially uniform layer of braze binder 14 on the coated core 22 over the core 10 by first/odd agitation.

Similarly, the proportion and amount of the powder composition 34 relative to the coated core 22 is preferably selected to provide a uniform or substantially uniform coating of the powder composition 34 on the green preform 40 by a second/even number of agitations on the green preform 40.

The stirring can be performed manually, but is preferably performed automatically. Agitation may include any shaking motion of the container 12 that causes mixing of the core 10 with the applied braze binder 14 or powder composition 34. In some embodiments, the agitation is performed in a three-dimensional shaking mixer. In some embodiments, the shaking mixer is

Shaker mixer (baseville a bahophen, Switzerland (Willy a. bachofen AG, Basel, Switzerland)). In some embodiments, the agitation is performed on a two-dimensional shaking table.

After sintering, the hybrid pre-sintered preform 60 may be used directly in a brazing processor, or may be ground prior to brazing or use in production.

While the invention has been described with reference to one or more embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the appended claims. Moreover, all numbers expressing quantities of ingredients in specific embodiments are to be understood as being modified in all instances by the term "about.