Braze joints for component and methods of forming the same

Abstract

To provide a system (200, 300, 400, 500) for creating a braze joint (202).SOLUTION: A system includes an environment (206) operable to reach a braze temperature sufficient to melt at least a portion of a braze material (218). The system also includes a component (204) within the environment (206). The component (204) includes a base (210) having a base surface (212), a recess (214) suspended from the base surface (212) into the base (210) to an inner edge (224), and a braze material (218) being within the recess (214) and forming a cap (220) above the base surface (212). The braze material (218) fills the recess (214) from the cap (220) to the inner edge (224). The cap (220) has an exposed braze surface (222). The system also includes an insulation layer (302) that at least partially covers the exposed braze surface (222).SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The field of the disclosure relates generally to brazing joints for metal alloys, and more specifically to thermal control of the brazing process. [Background technology]

[0002] Overall from metal alloys or For at least some known components that are partially fabricated, cracks may form in the alloy during normal use of the component. or For example, at least some known rotary machines use stainless steel for components that are used in the high temperature flow paths of the rotary machine during operation. and Nickel-based, Cobalt-based and Uses iron-based superalloys. High temperature flow paths provide thermal protection to components. and / or Mechanical stress and This causes strain and therefore cracks in the alloys of these components. or When defects occur, cracks are repaired or Defects are caused by high temperatures, stress, and and It must be able to withstand strain as well.

[0003] Cracks in alloys or One known method of repairing the defects is to create a brazed joint using a brazing process. and In some known nickel-based superalloys, such as CMSX-6® (registered trademark of Cannon Muskegon Corporation), a typical technique for salvaging damaged components is the use of brazing. In a conventional brazing process, a brazing material is used to fill the gap with liquid or At least one known brazing method repairs defects in an existing component by partially filling it with liquid brazing material and then allowing the brazing material to solidify. At least one known brazing method involves cleaning the defective surfaces to be joined, placing the defective components in a vacuum brazing furnace, and allowing the brazing material to melt and solidify. orIt involves heating a furnace to a target temperature so that it is partially melted, and then allowing the brazing material to flow into the space that will form the defect. The brazing process can be used to fill the gap between two components to join them together, or The brazing material may be used to form the new component.

[0004] In at least some of the known brazing processes for forming the above-mentioned brazed joints, solidification shrinkage occurs within the joint as the braze material begins to cool after it fills the defect in the component. Additionally, in at least some known brazed joints, as the braze material cools, the braze material closer to the surface of the metal alloy cools faster than the braze material deeper in the defect. This differential cooling, combined with solidification shrinkage, can result in a high degree of porosity. and / or This can result in solidification defects such as brazed joints with hot cracks. In at least some known brazing processes, when the gap filled with the brazing material is larger than 0.1 mm and the brazing material is a blend of a superalloy powder and a much lower melting point braze filler, porosity can form. In at least some known brazing processes, when the gap filled with the brazing material is less than 0.1 mm and the brazing material is a pure braze filler, hot cracks can occur. These defects in the brazed joints reduce the tensile strength of the brazed joint and shorten the creep life. and This can result in reduced fatigue life, which can increase wear on alloy-containing components and force turbine shutdowns. or This can cause additional wear on other internal components. These problems associated with defects in brazed joints can be particularly problematic for components designed for use in high stress areas, such as within the high temperature flowpaths of a rotary engine. Summary of the Invention

[0005] In one aspect, a system for producing a brazed joint is provided, the system including an environment operable to reach a brazing temperature sufficient to melt at least a portion of a braze material, the system also including components within the environment, the components including a base having a base surface, a recess depending into the base from the base surface to an inner edge, and The system includes a component including a braze material within the recess and forming a cap on the base surface. The braze material fills the recess from the cap to the inner edge. The cap has an exposed braze surface. The system also includes a braze material at least partially covering the exposed braze surface. Insulation The layer includes:

[0006] In another aspect, a method is provided for brazing a recess defined in a base. The recess depends into the base from a surface to an inner edge. The method includes creating a cap of brazing material over the recess. The cap has an exposed brazing surface. The method further includes positioning an insulating layer over the exposed brazing surface. The method also includes heating the brazing material in an environment to create an at least partially molten brazing material. The method further includes cooling the at least partially molten brazing material to form a solid braze joint in the recess.

[0007] In another aspect, a method is provided for brazing a recess defined in a base. The recess depends into the base from a base surface to an inner edge of the base. The method includes delivering at least partially molten braze material from a cap to the inner edge and into the recess. The method also includes extracting heat from a location on the base, the location being closer to the inner edge of the recess than the cap.

[0008] These aspects of the present disclosure and Other features, aspects, and Advantages will be better understood from the following detailed description when taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts throughout the drawings, in which: [Brief description of the drawings]

[0009] [Figure 1] 1 is a schematic diagram of an exemplary rotating machine. [Diagram 2] 1 is a cross-sectional view of an exemplary system for producing a braze joint in a component. [Diagram 3] 4 is a cross-sectional view of another exemplary system for producing a braze joint in a component. [Figure 4] 4 is a cross-sectional view of another exemplary system for producing a braze joint in a component. [Diagram 5] 4 is a cross-sectional view of another exemplary system for producing a braze joint in a component. [Figure 6] 1 is a flow diagram of an exemplary method for producing a brazed joint. [Figure 7] 4 is a flow diagram of another exemplary method for producing a brazed joint. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Unless otherwise indicated, the drawings provided herein illustrate features of embodiments of the present disclosure. These features are illustrative of one aspect of the present disclosure. or It is contemplated that the drawings may be applicable in a wide variety of systems comprising multiple embodiments, and therefore the drawings are not intended to include all conventional features known to those of ordinary skill in the art to be required for the practice of the embodiments disclosed herein.

[0011] The following specification and In the claims, reference will be made to a number of terms that shall be defined to have the following meanings.

[0012] Singular "one (a, an)" and "The" includes plural references unless the context clearly dictates otherwise.

[0013] As used herein, unless otherwise indicated, "generally," "substantially," andWords expressing approximations, such as "approximately," are used to express dissatisfaction with the terms so modified. or It indicates that the term "approximately" can be used to describe a range of conditions, not to a perfect degree, but only to an approximate degree as would be recognized by a person skilled in the art. and Values ​​modified by terms such as "substantially" are not intended to be limited to the exact value stated. In at least some instances, approximating language can correspond to the precision of an instrument for measuring the value. and This specification and Throughout the claims, range limits may be specified. Such ranges include, but are not limited to, combinations. and / or Substitution is possible and context or Unless the language indicates otherwise, the terms "first," "second," and the like are used herein merely as labels and do not denote any particular order, position, or location of the items to which they refer. or No hierarchical requirement is intended to be imposed. Further, for example, a reference to a "second" item may refer to, for example, a "first" or lower-numbered item, or It does not require the presence of a "third" or higher-numbered item, or It is not something to be excluded.

[0014] The system described herein and The method relates to producing a brazed joint in a component. Specifically, in an exemplary embodiment, the system includes an environment operable to reach a brazing temperature sufficient to melt at least a portion of a braze material. The system also includes a component in the environment, the component having a base having a base surface, a recess depending from the base surface to an inner edge into the base, and The system further includes a component including a braze material within the recess and forming a cap on the base surface. The braze material fills the recess from the cap to the inner edge. The cap has an exposed braze surface. In some embodiments, the system also includes a braze material that at least partially covers the exposed braze surface of the cap. InsulationAfter the environment is heated to the brazing temperature, the system Insulation Facilitates less rapid heat dissipation from the exposed brazing surface of the cap compared to systems without the layer. or Alternatively, the system includes a cooling system operable to extract heat from the base at a location closer to an inner edge of the recess than the cap, which facilitates more rapid cooling of the brazed joint compared to the exposed brazing surface of the cap. Thus, the system may be configured to reduce or eliminate solidification defects in the recess during the brazing process compared to the cap extending above the base surface. or This facilitates the production of completely free brazed joints.

[0015] 1 is a schematic diagram of an exemplary rotary machine, or turbomachine, or more specifically, a turbine engine, 100. In the exemplary embodiment, rotary machine 100 is a gas turbine engine. or , Rotary machines include, but are not limited to, steam turbine engines, gas turbofan aircraft engines, other aircraft engines, wind turbines, compressors, and Any other turbine engine, including a pump and / or In the exemplary embodiment, the turbine engine 100 includes an intake section 102, a compressor section 104 coupled downstream from the intake section 102, a combustor section 106 coupled downstream from the compressor section 104, a turbine section 108 coupled downstream from the combustor section 106, and a turbine section 108 coupled downstream from the combustor section 106. and The turbine section 108 includes an exhaust section 110 coupled downstream from the turbine section 108. The turbine section 108 is coupled to the compressor section 104 via a rotor shaft 112. As used herein, the term "couple" refers to a direct mechanical, thermal, electrical, or other connection between components. and / or Indirect mechanical, thermal, electrical, and / or mechanically connected components may be connected in a variety of ways, including but not limited to flow communication connections. and / orIt should be noted that the flow communication connections may also include a rotor shaft 112. In the exemplary embodiment, the combustor section 106 includes a plurality of combustors 114. The combustor section 106 is coupled to the compressor section 104 such that each combustor 114 is in flow communication with the compressor section 104. The rotor shaft 112 is coupled to a generator, such as, but not limited to, a power generator. and / or The compressor section 104 is further coupled to a load 116, such as a mechanical drive application. and Each of the turbine sections 108 includes at least one rotor assembly 118 coupled to the rotor shaft 112. Each rotor assembly 118 of the turbine sections 108 includes a number of circumferentially arranged, radially extending turbine blades 119.

[0016] During operation, the intake section 102 channels air 120 towards the compressor section 104. The compressor section 104 compresses the intake air 120 to a higher pressure before discharging the compressed air 122 towards the combustor section 106. The compressed air 122 is channeled to the combustor section 106 where it is mixed with a fuel (not shown) and combusted to generate hot combustion gases 124. The combustion gases 124 are channeled downstream towards the turbine section 108 where they impinge upon the turbine blades 119 and the thermal energy is converted to mechanical rotational energy that is used to drive the rotor assembly 118 about a longitudinal axis 126. Often, the combustor section 106 and The turbine section 108 is referred to as the hot gas section 109 of the turbine engine 100. The exhaust gases 128 are then discharged through an exhaust section 110 to the surrounding atmosphere.

[0017] In some embodiments, during operation of the turbine engine 100, the turbine blades 104 may be rotated by, for example, but not limited to, stator vanes (not shown) and Components 204 in the hot gas section 109, such as turbine blades 119, which may include shrouds (not shown), may be exposed to high temperatures, for example, 1250 degrees Celsius, creating thermal stresses. In the turbine section 108, the components 204 also experience stresses from high speed rotation. and During operation, the components are subjected to mechanical stresses, such as the ejection of high velocity hot gases from the combustor 106. Such extreme operating conditions can lead to creep. and / or Fatigue cracks, and This may cause other defects to form in the components 204 of the hot gas section 109, requiring repair.

[0018] FIG. 2 illustrates one of the components 204. or 2 is a cross-sectional view of a system 200 for creating a brazed joint 202 in a plurality of components 204. While components 204 are described as components of rotating machine 100 for purposes of illustration, it should be understood that system 200 is also contemplated for creating brazed joints in any suitable components 204 in a wide variety of applications and is not limited to use with the components of rotating machine 100 described herein.

[0019] In some embodiments, the component 204 may be a component in the hot gas section 109 of the turbine engine 100. or The component 204 is formed from a metal alloy used in the combustor 106. In some such embodiments, the component 204 is a cobalt-based or For example, the component 204 may be fabricated from a single crystal nickel-based superalloy, such as CMSX-4®. In an alternative embodiment, the component 204 is fabricated from a single crystal nickel-based superalloy, such as CMSX-4®. and It may be formed from any alloy that can be brazed using the method.

[0020] The system 200 includes an environment 206 for producing the brazed joint 202. In some embodiments, the environment 206 is a cavity defined within a heating compartment 208. In an exemplary embodiment, the heating compartment 208 is a vacuum furnace configured to provide both heat and vacuum to the cavity during the brazing process. For example, the heating compartment 208 is configured to provide a uniform temperature throughout the environment 206 and to draw a sufficient vacuum within the environment 206 to remove at least some gases present in the environment 206. In one embodiment, such gases include oxygen, nitrogen, carbon dioxide, water vapor, and In alternative embodiments, the environment 206 is any suitable environment that enables a braze joint to be formed in the component 204 as described herein.

[0021] The component 204 includes a base 210 having a base surface 212 and a recess 214 depending from the base surface 212 to an inner edge 224 within a recess depth 216. In the exemplary embodiment, the recess 214 represents a defect, such as a crack, in the base 210 that may occur during normal use of the component 204. The inner edge 224 is the innermost portion of the crack from the base surface 212. or For example, in an embodiment in which component 204 is formed from a metal alloy for use in the hot gas section 109 of turbine engine 100, recesses 214 may be formed from a metal alloy that is capable of withstanding rotational stresses, forces from the fast moving hot gas stream, and / or The recesses 214 may be formed by a combination of cyclical thermo-mechanical strains on the component 204. In an alternative embodiment, the recesses 214 may be formed by a combination of cyclical thermo-mechanical strains on the component 204. or During the machining process, or Intentionally by another process, such as during bonding to bond two separately formed components 204 together or It may be formed unintentionally.

[0022] The braze joint 202 is formed from a braze material 218. In one embodiment, the braze material 218 includes a pure braze filler alloy, such as DF-4B diffusion braze alloy. Braze filler alloys include any of the following alloys: aluminum, silicon, copper, silver, germanium, gold, nickel, cobalt, and One of boron or In an exemplary embodiment, the braze alloy is a multi-component eutectic having a relatively low melting point compared to the component 204. For example, a cobalt-based and Braze alloys used for components 204 formed from nickel-based superalloys typically have melting temperatures below 1120 degrees Celsius, and more specifically, between 900 and 1100 degrees Celsius. In another embodiment, the braze material 218 includes a blend of a braze powder and a braze filler alloy. The braze powder is typically a superalloy for the component 204 and provides higher strength compared to the braze filler alloy. and Thus, at a certain temperature, the braze alloy is molten but the braze powder is solid, producing a partially molten braze material 218. In an alternative embodiment, the braze material 218 is completely or may consist essentially of a braze filler alloy; or It may include other materials that enable the braze joint 202 to be formed as described herein.

[0023] In one embodiment, the braze material 218 is a braze filler alloy that is mixed with a binder to create a braze paste. and Braze powders, including but not limited to braze filler alloys and The braze powder is mixed with 8 percent binder. The braze paste is a semi-solid, which in some embodiments allows the braze material 218 to be poured or injected into the recesses 214. Such a filling technique is particularly suitable for recesses 214 that are wider than 0.1 millimeters. In an alternative embodiment, the braze paste orA pure braze filler alloy can be placed over the recesses 214 to create a cap 220, allowing the braze material 218 to flow into the recesses by capillary effect. Such a filling technique is particularly suitable for recesses 214 of 0.1 millimeters or less.

[0024] In some embodiments, during the brazing process, the environment 206 is heated to a brazing temperature. In some embodiments, the environment 206 is held at the brazing temperature for between 10 minutes and 120 minutes. In some such embodiments, the environment 206 is held at the brazing temperature for between 20 minutes and 40 minutes, and in some such embodiments, for 30 minutes. or The environment 206 may be maintained at the brazing temperature for any suitable length of time. The brazing temperature may be below the melting temperature of the components 204 to melt the brazing material 218 as described above or to or In an exemplary embodiment in which the brazing material 218 comprises a brazing paste, at the brazing temperature the brazing alloy melts but the brazing powder remains solid, producing a partially molten brazing material 218. In some such embodiments, the brazing temperature is maintained at a constant temperature until the brazing temperature is reached, at which point the brazing material 218 is heated to a temperature above the brazing temperature. or A paste braze material 218 is placed into the recess 214, filling the recess from the inner edge 224 to the base surface 212. In some such embodiments, additional braze material 218 is placed on top of the base surface 212 to create a cap 220. The cap 220 is in fluid communication with the braze material 218 in the recess 214. The braze material 218 is then heated to a brazing temperature, removing most of the binder present. or All are combusted, causing the braze material 218 to at least partially melt.

[0025] As mentioned above, in an alternative embodiment, the brazing paste or A pure braze alloy can be placed over the recess 214 to create a cap 220, and the capillary effect can allow the braze material 218 to flow into the recess 214. Filling of the recess 214 can occur at room temperature or orThis can occur by heating the environment 206 to a brazing temperature. In an exemplary embodiment, the brazing material 218 is heated to a brazing temperature, causing the exposed brazing surface 222 on the cap 220 to at least partially melt. and 2. Create a contact angle 219 between the partially molten braze material 218 and the recess 214. In some such embodiments, the pure braze filler contacts the base surface 212, the inner edge 224, and the recess 214. and 214. In a further embodiment, the contact angle 219 is 30 degrees or less and the braze material wets the inner edge 224 of the recess 214. and The braze material 218 may be spread over the other surfaces, allowing capillary effect to draw the braze material 218 into the recess 214. In an alternative embodiment, the braze material 218 is completely melted at the brazing temperature. or In an additional embodiment, the braze material 218 may be placed on the base surface 212 over the recess 214 in a partially molten state and fed into the recess 214 by capillary effect. In a further embodiment, the braze material 218 may fill only a portion of the recess 214 such that the cap 220 is drawn into the recess 214 when the braze material is heated to a brazing temperature in the environment 206.

[0026] In some embodiments, after the brazing material 218 reaches the brazing temperature and at least partially melts and completely fills the recess, the temperature in the environment 206 can be reduced and the brazing material 218 can be cooled to solidify the brazing material 218 and create the brazed joint 202 in the recess 214. In some embodiments, the solidification of the brazing material 218 causes the brazing material 218 to shrink, which can result in solidification defects 228 in the brazed joint 202. Some such solidification defects 228 include high porosity (both amount and size) in the solid brazed joint 202, as shown by the pores 227 in FIG. 2. Other solidification defects 228 include linear indications, as shown by the linear indications 229, or In some embodiments, the base 210 andAs the braze material 218 begins to cool, the exposed braze surface 222 or A first portion 230 of the braze material 218 located adjacent the inner edge 224 or The first portion 230 cools faster than the second portion 232 of the braze material 218 located nearby. When one portion of the braze material 218 cools faster than another portion, for example, if the first portion 230 cools faster in the environment 206 than the second portion 232, defects 228 may form due to solidification shrinkage. In the exemplary embodiment, the first portion 230 cools faster than the second portion 232, causing solidification defects 228 to form in the solidified braze material 218 near the second portion 232. When the component 204 including the braze joint 202 is returned to service, at least some of these known solidification defects 228 may result in a reduction in the tensile strength of the braze joint 202, and Shorter creep life and This results in fatigue life.

[0027] In some embodiments, the size of the cap 220 compared to the size of the braze joint 202 may affect the ability of the cap 220 to cause the braze material 218 in the recess 214 to shrink during cooling. Modulus Cap 220 against Modulus can be used to characterize how effectively the cap 220 feeds the braze joint 202, where: Modulus is the volume of a geometric object. Heat Dissipation By area The divided value For example, Modulus If the ratio is less than 1.0, the braze material 218 in the cap 220 will begin and complete solidification sooner than the braze material 218 in the recess 214 while cooling in the environment 206. In one embodiment, the ratio of the braze joint 202 greater than 1.0 Modulus Cap 220 against ModulusThe ratio of 0.1 to 0.5 effectively distributes the braze material 218 within the recess 214 and at least partially compensates for shrinkage during cooling. In some embodiments, the ratio of 0.1 to 0.5 of the braze joint 202 is greater than 1.1. Modulus Cap 220 against Modulus The ratio of 0.1 to 0.5 effectively distributes the braze material 218 into the recess 214 during cooling to at least partially compensate for shrinkage and reduce solidification defects 228. In a further embodiment, the ratio of 0.1 to 0.5 of the braze joint 202 greater than 1.5 is preferred. Modulus Cap 220 against Modulus A ratio of 0.1 to 0.5 is particularly effective at delivering braze material 218 into recess 214 during cooling to at least partially compensate for shrinkage and reduce solidification defects 228. In an alternative embodiment, a ratio of 0.1 to 0.5 of braze joint 202 greater than 1.5 is particularly effective at delivering braze material 218 into recess 214 during cooling to at least partially compensate for shrinkage and reduce solidification defects 228. Modulus Cap 220 against Modulus This ratio provides braze material 218 into recess 214 during cooling to fully compensate for shrinkage and eliminate solidification defects 228 in braze joint 202. or Alternatively, increasing the contact angle 219 at the base surface 212 may reduce the contact angle of the cap 220. Modulus 2. Effectively, the size of the cap 220 is increased, increasing the supply of braze material 218 from the cap 220 to the recess 214 during cooling, at least partially compensating for the shrinkage. and The contact angle 219 is modified to enhance delivery of the cap 220 into the recess 214 during cooling.

[0028] 3 is a cross-sectional view of another exemplary embodiment of a system for producing a brazed joint 202 in a component 204, referred to as system 300. System 300 is similar to system 200, and thus like components are labeled similarly to system 200. System 300 differs from system 200 in that system 300 includes an insulating layer 302 that at least partially covers the exposed brazing surface 222 of cap 220 of brazing material 218. In the exemplary embodiment, insulating layer 302 is disposed over cap 220. and2, the braze material 218 is heated to a brazing temperature, at least partially melting the braze material 218 and allowing the braze material 218 to enter the recess 214. In some embodiments of the system 300, prior to heating the braze material 218 to the brazing temperature, or After the braze material 218 is at least partially melted, the insulating layer 302 is placed over the exposed braze surface 222 such that the insulating layer 302 at least partially covers the exposed braze surface 222 .

[0029] The insulating layer 302 may include any material that enables the insulating layer 302 to function as described herein. In some embodiments, the insulating layer 302 is made of a ceramic material, ceramic fiber, mineral wool, polycrystalline fiber, silica cloth, and Any combination of them or Formed from multiple.

[0030] Similar to system 200, in the exemplary embodiment of system 300, once component 204 has been heated for a sufficient time to produce at least partially molten brazing material 218 within environment 206, environment 206 is allowed to cool from the brazing temperature. As environment 206 cools, base 210 and The braze material 218 also begins to cool, allowing the braze material 218 to solidify and form the braze joint 202. Unlike the system 200, in some embodiments, the insulating layer 302 is disposed over the cap 220. and The first portion 230, located near the brazing surface 222, is allowed to cool slower than the second portion 232, located near the inner edge 224. Due to the temperature difference between the first portion 230 and the second portion 232, solidification of the brazing material 218 begins sooner near the second portion 232 than near the first portion 230. and2. The brazing process is completed. Thus, when shrinkage occurs in the braze material 218 during solidification, any solidification defects 228 that form in the braze material 218 occur closer to the first portion 230 than to the second portion 232. More specifically, in an exemplary embodiment, the insulating layer 302 causes the solidification defects 228 to form primarily in the cap 220 near the exposed brazing surface 222. Before the component 204 is returned to service, the cap 220 is removed or, in some cases, is not designed to contribute to the strength of the braze joint 202. Thus, in some embodiments, the solidification defects 228 in the first portion 230 of the braze material 218 do not significantly affect the performance of the braze joint 202.

[0031] As with system 200, in system 300, varying the size of cap 220 relative to the size of brazed joint 202 in combination with applying thermal insulation layer 302 may affect the ability of cap 220 to deliver braze material 218 into recess 214 to at least partially compensate for shrinkage during cooling. Modulus Cap 220 against Modulus can be used to characterize how effectively the cap 220 feeds the brazed joint 202. In some further embodiments, the insulating layer 302 is a Insulation of the cap 220 compared to the corresponding ratio for the cap 220 without the layer. Modulus , and therefore the brazed joint 202 Modulus In some such embodiments, the insulating layer 302 increases the ratio of the cap 220 having a narrower width to the cap 220 having a wider width. Insulation This allows for the same supply of braze joints 202 as a cap 220 without the layer.

[0032] 4 is a cross-sectional view of another exemplary embodiment of a system for producing a brazed joint 202 in a component 204, referred to as system 400. System 400 is similar to system 200, and thus like components are labeled similarly to system 200. System 400 differs from system 200 in that system 400 includes a cooling device 401 operable to extract heat from a location 403 on base 210. More specifically, location 403 is closer to inner edge 224 of recess 214 than cap 220.

[0033] In the exemplary embodiment, the cooling device 401 includes a heat conducting element 402 in contact with the location 403. Also, in the exemplary embodiment, the location 403 is a second base surface 404 of the base 210 opposite the base surface 212. However, it will be appreciated that the location 403 may be any location that is closer to the inner edge 224 of the recess 214 than the cap 220. In other words, the location 403 is a location where the cooling device 401 can facilitate the heat extraction of the second portion 232 of the braze material 218. Enhance On the other hand, it is selected to have less effect on the first portion 230 of the braze material 218 .

[0034] Similar to system 200, in an exemplary embodiment of system 400, after component 204 is heated for a sufficient time to generate at least partially molten brazing material 218 in environment 206, environment 206 is allowed to cool from the brazing temperature. In an exemplary embodiment, heat conducting element 402 is configured to extract heat from location 403 of base 210 while environment 206 is cooling. In an alternative embodiment, heat conducting element 402 is configured to extract heat from location 403 of base 210 while environment 206 is actively heating environment 206 and then while environment 206 is cooling. Because heat conducting element 402 is located closer to second portion 232 than first portion 230, brazing material 218 drops in temperature faster near second portion 232 than first portion 230. Due to the temperature difference between first portion 230 and second portion 232, solidification of brazing material 218 occurs more rapidly near second portion 232 than first portion 230. Thus, when shrinkage occurs in the braze material 218 during solidification, any solidification defects 228 that form in the braze material 218 occur closer to the first portion 230 than to the second portion 232. In an exemplary embodiment, the solidification defects 228 form primarily in the cap 220 near the exposed braze surface 222. Before the component 204 is returned to service, the cap 220 is removed or, in some cases, is not designed to contribute to the strength of the braze joint 202. Thus, the solidification defects 228 in the first portion 230 of the braze material 218 do not significantly affect the performance of the braze joint 202.

[0035] The heat conducting element 402 may be any heat conducting material that enables the heat conducting element to function as described herein. and / or In some embodiments, the heat transfer element 402 includes a heat exchanger. The heat transfer element 402 may be, for example, a plate fin heat exchanger, a plate heat exchanger, orIn yet another embodiment, the heat conducting element 402 comprises a graphite plate with embedded cooling channels connected to a cooling medium. In alternative embodiments, the cooling device 401 comprises any suitable structure that enables the system 400 to function as described herein.

[0036] 5 is a cross-sectional view of another exemplary system for producing a brazed joint 202 in a component 204, referred to as system 500. System 500 is similar to system 400, and thus like components are labeled the same as system 400. System 500 differs from system 400 in that cooling device 401 is implemented as an impingement manifold 502 configured to impinge fluid 504 with base 210 at location 403. As noted above, location 403 is where fluid 504 impinges on cap 220, exposed brazing surface 222, and the inner edge 224 of the recess 214 than the first portion 230; and The location 403 is selected to impinge on a portion of the base 210 that is proximate to the second portion 232. In the illustrated embodiment, the location 403 is again on a second base surface 404 of the base 210 opposite the base surface 212. or , location 403 can be any location closer to inner edge 224 of recess 214 than cap 220 .

[0037] Similar to system 200, in an exemplary embodiment of system 500, after component 204 is heated for a sufficient time to produce at least partially molten brazing material 218 in environment 206, environment 206 is allowed to cool from the brazing temperature. Impingement manifold 502 is configured to deliver fluid 504 to extract heat from location 403 of base 210 while environment 206 cools. Because fluid 504 impinges on base 210 at location 403 closer to second portion 232 than first portion 230, brazing material 218 drops in temperature more quickly near second portion 232 than first portion 230. Due to the temperature difference between first portion 230 and second portion 232, solidification of brazing material 218 occurs more rapidly near second portion 232 than first portion 230. Thus, when shrinkage occurs in the braze material 218 during solidification, any solidification defects 228 that form in the braze material 218 occur closer to the first portion 230 than to the second portion 232. In an exemplary embodiment, the solidification defects 228 form primarily in the cap 220 near the exposed braze surface 222. Before the component 204 is returned to service, the cap 220 is removed or, in some cases, is not designed to contribute to the strength of the braze joint 202. Thus, the solidification defects 228 in the first portion 230 of the braze material 218 do not significantly affect the performance of the braze joint 202.

[0038] Collision manifold 502, and The fluid 504 delivered thereby may be any heat convection system that enables the cooling device 401 to function as described herein. and / or In some embodiments, the impingement manifold 502 includes jet nozzles connected to a source of fluid 504, such as a pressurized gas. In some such embodiments, the fluid 504 is argon, helium, hydrogen, and / or Nitrogen One or Includes multiple.

[0039] Insulation Layer 302 (shown in FIG. 3) andCooling device 401 (FIG. 4 and 5) are shown above as being implemented separately, but in some embodiments may be used to reduce solidification defects 228 from the brazed joint 202. or An additional benefit of elimination is that Insulation layer 302 and This is obtained by simultaneously implementing a cooling device 401. In other words, during the cooling phase after the environment 206 is heated to the brazing temperature, Insulation The layer 302 includes a cooling device 401 (e.g., a heat conducting element 402 ) that operates to extract heat from a location 403 of the base 210 . or The impingement manifold 502 simultaneously at least partially covers the exposed brazing surface 222 of the cap 220 , further facilitating more rapid solidification of the brazing material 218 near the second portion 232 than the first portion 230 .

[0040] FIG. 6 is a flow diagram of an exemplary method 600 of brazing a recess defined in a base, such as brazing recess 214 (shown in FIGS. 2-5) defined in base 210. The recess depends into the base from a base surface, such as base surface 212, to an inner edge, such as inner edge 224. The method 600 includes producing 602 a cap, such as cap 220 of brazing material, such as brazing material 218, over the recess. The cap has an exposed brazing surface, such as exposed brazing surface 222. The method 600 further includes positioning 604 an insulating layer, such as insulating layer 302, over the exposed brazing surface. The method 600 further includes heating 606 the brazing material in an environment, such as environment 206, to produce at least partially molten brazing material. The method 600 further includes cooling 608 the at least partially molten brazing material to form a solid brazing joint, such as brazed joint 202.

[0041] Brazing materials include brazing filler alloys, brazing powders, and In some embodiments where the brazing paste includes a binder, creating 602 a cap of brazing material over the recess may include forming a cap of brazing material over the recess. andand filling the recess from the surface to the inner edge with brazing paste such that the brazing paste is in fluid communication. In further embodiments, heating the brazing material in the environment to generate 606 the at least partially molten brazing material further includes filling the recess to the inner edge with the at least partially molten brazing material from the cap via capillary effect. In certain embodiments, cooling the at least partially molten brazing material and forming the brazed joint 608 further includes passively allowing the environment to cool.

[0042] In some embodiments, cooling 608 the at least partially molten braze material includes cooling a location on the base closer to the inner edge than the cap. In certain embodiments, cooling 608 the at least partially molten braze material further includes solidifying the cap. In some such embodiments, the solid cap has greater porosity than the solid braze joint.

[0043] 7 is a flow diagram of another exemplary method 700 of brazing a recess defined in a base, such as brazing recess 214 in base 210 (shown in FIGS. 2-5). The recess depends into the base from a base surface, such as base surface 212, to an inner edge, such as inner edge 224. The method 700 includes providing 702 at least partially molten brazing material, such as brazing material 218, from a cap, such as cap 220, to the inner edge and into the recess. The method 700 also includes extracting 704 heat from the base at a location on the base that is closer to the inner edge of the base than the base surface.

[0044] In some embodiments, extracting 704 heat from the base includes conductive cooling at locations on the base using a heat exchanger, while in other embodiments, extracting 704 heat from the base includes convection cooling at locations on the base using impingement cooling.

[0045] In some embodiments, method 700 further includes positioning an at least partially solid braze material over the recess in an environment, such as environment 206. In some such embodiments, providing 702 the at least partially molten braze material from the cap to the recess further includes heating the environment to a brazing temperature to produce the at least partially molten braze material.

[0046] In certain embodiments, the method 700 further includes positioning an insulating layer, such as insulating layer 302, on an exposed brazing surface, such as exposed brazing surface 222, on the cap prior to providing the at least partially molten brazing material to extract heat from the base.

[0047] The above system for producing a brazed joint in a component and The method is characterized by the fact that fewer defects are formed in the joint during the brazing process. or This makes it easier to create brazed joints in components without any need for replacing the brazed joints, thus increasing the life of the components with brazed joints. and The method provides a high degree of metallurgical integrity and imparts superior and reliable mechanical capabilities to the brazed joint. and The method comprises the steps of: and Extreme heat, such as components exposed to rotational stresses and This can be particularly advantageous for components used in high mechanical stress environments.

[0048] In addition, the systems described herein and Exemplary technical effects of the method include at least one of the following: (a) reducing defects in a braze joint due to solidification shrinkage; (b) reducing the amount of braze material required to feed into a recess when forming a braze joint in a component; and (c) Extending the life of brazed joints.

[0049] System for brazing joints in components - Patents.com andExemplary embodiments of the method are described in detail above. and The system is not limited to the particular embodiments described herein, but rather the components of the system and / or The method steps may include any of the other components described herein. and / or For example, the present system may be used independently and separately from the steps. and The methods may be used in conjunction with many types of components and are not limited to practice with only the gas turbine engines described herein. Rather, the exemplary embodiments may be implemented in connection with many other joining / brazing applications. and It can be used.

[0050] Although specific features of various embodiments of the present disclosure may be shown in some drawings and not in others, this is for convenience only, and in accordance with the principles of the embodiments of the present disclosure, any feature of a drawing may be referenced in combination with any feature of any other drawing. and / or A patent may be claimed.

[0051] This written description uses examples to disclose embodiments of the present disclosure, including the best mode, and also to enable any person skilled in the art to practice embodiments of the present disclosure, and is not intended to be limiting unless otherwise specified. or This includes making and using the system and practicing any incorporated methods. The patentable scope of the embodiments described herein is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples may include, but are not limited to, those having structural elements that do not differ from the literal language of the claims. or It is intended that the claims include equivalent structural elements that do not differ substantially from the literal language of the claims. [Explanation of symbols]

[0052] 100 Rotating machines, turbine engines 102 Intake section 104 Compressor Section 106 Combustor section, combustor 108 Turbine Section 109 Hot Gas Section 110 Exhaust Section 112 rotor shaft 114 Combustor 116 Load 118 Rotor Assembly 119 Turbine Blade 120 Intake air 122 Compressed Air 124 Hot Combustion Gases 126 Longitudinal Axis 128 Exhaust Gas 200 Systems 202 Brazed joint 204 Components 206 Environment 208 Heated Compartment 210 base 212 Base surface 214 Recess 216 Recess depth 218 Brazing Materials 219 Contact angle 220 Cap 222 Exposed brazing surface 224 Common-law marriage 227 Pore 228 Solidification Defects 229 Linear indication pattern 230 First Part 232 Second Part 300 Systems 302 Insulation Layer, insulation layer 400 Systems 401 Cooling device 402 Heat Conduction Element 403 Location 404 Second Base Surface 500 Systems 502 Collision Manifold 504 Fluid 600 ways 602 Steps 604 Steps 606 Steps 608 Steps 700 methods 702 Steps 704 Steps

Claims

1. A system (200, 300, 400, 500) for producing a brazed joint (202), said system (200, 300, 400, 500) comprising: an environment (206) operable to reach a brazing temperature sufficient to melt at least a portion of the brazing material (218); A component (204) within the environment (206), a base (210) having a base surface (212); a recess (214) depending within said base (210) from said base surface (212) to an inner edge (224); and the brazing material (218) in the recess (214) and forming a cap (220) on the base surface (212), the brazing material (218) filling the recess (214) from the cap (220) to the inner edge (224), the cap (220) having an exposed brazing surface (222); a component (204) comprising: an insulating layer (302) at least partially covering the exposed brazing surface (222); A system (200, 300, 400, 500) comprising:

2. The system of claim 1 , wherein the braze material comprises a braze filler alloy.

3. 3. The system of claim 2, wherein the brazing material comprises a brazing paste including the brazing alloy and a brazing powder, the brazing powder having a higher melting point than the brazing filler alloy.

4. 10. The system of claim 1, wherein the insulating layer comprises at least one of ceramic, ceramic fiber, mineral wool, polycrystalline fiber, and silica cloth, and the insulating layer completely covers the cap and at least partially covers the base surface.

5. 10. The system (200, 300, 400, 500) of claim 1, further comprising a cooling device (401) operable to extract heat from a location (403) on the base (210), the location (403) being closer to the inner edge (224) of the recess (214) than the cap (220).

6. 2. The system of claim 1, wherein the insulating layer is configured such that the ratio of the elastic modulus of the cap to the elastic modulus of the brazed joint is 1.1 or greater, the elastic modulus being defined as the volume of a geometric object divided by the heat dissipation area of ​​the geometric object.

7. A method (600) for brazing a recess (214) defined in a base (210), the recess (214) depending within the base (210) from a base surface (212) of the base (210) to an inner edge (224), the method (600) comprising: creating (602) a cap (220) of brazing material (218) over the recess (214), the cap (220) having an exposed brazing surface (222); positioning (604) a thermal barrier (302) on the exposed brazing surface (222); heating (606) the braze material (218) in the environment (206) to produce an at least partially molten braze material (218); cooling (608) the at least partially molten braze material (218) to form a solid braze joint (202) within the recess (214); A method (600) comprising:

8. 8. The method of claim 7, wherein the brazing material is a brazing paste including a brazing filler alloy, a brazing powder, and a binder, and creating a cap of the brazing material over the recess further comprises filling the recess from the surface to the inner edge with the brazing paste such that the cap and the brazing paste within the recess are in fluid communication.

9. 8. The method of claim 7, wherein heating the brazing material in the environment to generate at least a partially molten brazing material further comprises filling the recess up to the inner edge with the at least a partially molten brazing material from the cap via capillary effect.

10. 8. The method of claim 7, wherein cooling the at least partially molten brazing material comprises cooling a location on the base that is closer to the inner edge than the cap.

11. 8. The method of claim 7, wherein cooling the at least partially molten braze material further comprises solidifying the cap, the solid cap having greater porosity than the solid braze joint.

12. A method (700) for brazing a recess (214) defined in a base (210), the recess (214) depending within the base (210) from a base surface (212) of the base (210) to an inner edge (224), the method (700) comprising: dispensing (702) at least partially molten brazing material (218) from a cap (220) to the inner edge (224) and into the recess (214); extracting heat (704) from a location (403) on the base (210), the location (403) being closer to the inner edge (224) of the recess (214) than the cap (220); A method (700).

13. 13. The method (700) of claim 12, wherein extracting (704) heat further comprises conductively cooling at the location (403) using a heat exchanger (402).

14. 13. The method (700) of claim 12, wherein extracting (704) heat further comprises impingement cooling at the location (403).

15. 13. The method of claim 12, further comprising positioning an at least partially solid brazing material over the recess in an environment, and wherein delivering the at least partially molten brazing material from the cap into the recess further comprises heating the environment to a brazing temperature to produce the at least partially molten brazing material.

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