A structural element and method for repairing a damaged portion of a metal component utilizes a preform configured to engage with the metal component and receive a repair material. The preform may be made of a material having a first melting point, and the repair material may be made of a material having a second melting point that is lower than the first melting point. The preform may be a mold configured to reconstruct the shape of the damaged portion of the metal component. The repair material may include a first material and an additive material, such as boron. The repair material may have a melting point that is approximately 40 degrees Fahrenheit lower than the melting point of the metal component.

In one aspect, a method for performing in situ repairs of internal components of a gas turbine engine may generally include inserting a repair tool through an access port of the gas turbine engine such that the repair tool includes a tip end positioned within the gas turbine engine and a material supply end positioned outside the gas turbine engine. The method may also include positioning the tip end of the repair tool adjacent to a defect of an internal component of the gas turbine engine, wherein the defect defines a fillable volume along a portion of the internal component. In addition, the method may include supplying a filler material to the tip end of the repair tool and expelling the filler material from the tip end of the repair tool such that the fillable volume is at least partially filled with the filler material.

In one aspect, a method for performing in situ repairs of internal components of a gas turbine engine may generally include inserting a repair tool through an access port of the gas turbine engine such that the repair tool includes a tip end positioned within the gas turbine engine and a material supply end positioned outside the gas turbine engine. The method may also include positioning the tip end of the repair tool adjacent to a defect of an internal component of the gas turbine engine, wherein the defect defines a fillable volume along a portion of the internal component. In addition, the method may include supplying a filler material to the tip end of the repair tool and expelling the filler material from the tip end of the repair tool such that the fillable volume is at least partially filled with the filler material.

A method for joining a filler material to a substrate material includes melting the filler material within a melting chamber of a crucible such that the filler material is molten. The crucible has an outlet fluidly connected to the melting chamber. The method also includes holding the filler material within the melting chamber of the crucible by applying a first pressure differential across the outlet of the crucible, and releasing the filler material from the melting chamber of the crucible by applying a second pressure differential across the outlet of the crucible to deliver the filler material to a target site of the substrate material. The second pressure differential has a different value than the first pressure differential.

A method for joining a filler material to a substrate material includes melting the filler material within a melting chamber of a crucible such that the filler material is molten. The crucible has an outlet fluidly connected to the melting chamber. The method also includes holding the filler material within the melting chamber of the crucible by applying a first pressure differential across the outlet of the crucible, and releasing the filler material from the melting chamber of the crucible by applying a second pressure differential across the outlet of the crucible to deliver the filler material to a target site of the substrate material. The second pressure differential has a different value than the first pressure differential.

Described is a thixotropic para-aramid gel that includes a polymer resin, an alkali-soluble anionic thickener, an adhesion promoter, and para-aramid pulp fibers. The polymer resin includes at least one of an acrylate copolymer and a styrene-acrylate copolymer. Also described is a method of producing the para-aramid gel for plaster reinforcement. The method includes mixing the polymer resin, the alkali-soluble anionic thickener, and the adhesion promoter to create a thixotropic gel, and then spinning para-aramid pulp fibers into the thixotropic gel using a high shear mixer. A method of reinforcing a plaster ceiling is also described. The method includes inserting a plurality of fasteners into a visible surface of the ceiling, leaving a portion of each fastener exposed at or above the visible surface, and applying a layer of the para-aramid-reinforced thixotropic gel to the visible surface and encapsulating the portion of each fastener within the layer.

A method of repairing defect in cast iron workpiece, including: machining the workpiece in the area of the defect to remove the defective material and form a chamber opening at a surface of the workpiece; anchoring a receptacle to the workpiece above the chamber (2), the receptacle is provided with an orifice in communication with the chamber; adding molten iron (4) into the receptacle so that it at least part of it flows into the chamber; adding slagging agent (5) into the receptacle; heating the slagging agent and the molten iron with an electrode (6); adding nodulizing agent into the molten iron so as to segregate graphite; and allowing the molten iron and the workpiece to cool down slowly. The above-described technique also has applicability for connecting two cast iron workpieces (11,12) together.

A method of repairing defect in cast iron workpiece, including: machining the workpiece in the area of the defect to remove the defective material and form a chamber opening at a surface of the workpiece; anchoring a receptacle to the workpiece above the chamber (2), the receptacle is provided with an orifice in communication with the chamber; adding molten iron (4) into the receptacle so that it at least part of it flows into the chamber; adding slagging agent (5) into the receptacle; heating the slagging agent and the molten iron with an electrode (6); adding nodulizing agent into the molten iron so as to segregate graphite; and allowing the molten iron and the workpiece to cool down slowly. The above-described technique also has applicability for connecting two cast iron workpieces (11,12) together.

A system and method of preparing a metal object for machining, wherein the metal object comprises at least two working portions that are to be machined and that are connected to remote sides or ends of an intermediate portion of the metal object, the method comprising: inserting the intermediate portion into a casting mold, such that the at least two working portions protrude from the casting mold; pouring a liquid metal material into the casting mold so as to cover the intermediate portion; allowing the liquid metal to cool, thereby forming a cast bulk surrounding the intermediate portion of the metal object; and removing the casting mold, whereby the cast bulk enables machining of the at least two working portions to be carried out while the second cast segment is being held.

A method of refurbishing a steel-shell brake drum that includes superheating a worn-out brake drum until the worn-out brake drum is glowing hot. The worn-out brake drum includes a steel shell and a worn-out, gray-iron layer bonded to an inside surface of the steel shell. The method further includes centrifugal casting additional molten iron to the gray-iron layer to increase the radial thickness of the gray-iron layer.