High-Temperature Brush Seal Using Gamma-Prime Superalloys

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional brush seals made from low-cost, finely drawn wires derived from nickel- or cobalt-based alloys struggle to consistently process higher gamma-prime precipitate superalloys into thin wires suitable for high-temperature gas turbine engines, compromising thermal and mechanical properties.

Innovation Solution

A brush seal configuration using precipitation hardened nickel superalloys, including single crystal superalloys, with a comb-like structure formed from sheet stock and optionally interspersed with superalloy wires, to effectively block high pressure differentials and withstand increased turbine temperatures while managing processing costs.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If conventional brush seals use low-cost, finely drawn wires from nickel- or cobalt-based alloys, then manufacturing cost is reduced and ease of manufacture is improved, but thermal and mechanical properties deteriorate under high temperature and pressure differentials

Engineering Contradiction:
Improveease of manufactureVSAvoidthermal and mechanical properties
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The patent changes the material parameters by transitioning from conventional nickel- or cobalt-based alloys to nickel-based superalloys with increased gamma-prime precipitate concentrations (at least 25 vol%, preferably at least 40 vol%). This parameter change enables the seal to withstand higher turbine temperatures and pressure differentials while maintaining manufacturing feasibility through controlled precipitation hardening processes

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent employs composite material strategy by creating a brush seal from superalloy wires that are composites themselves - nickel-based alloys with dispersed gamma-prime precipitates (Ni3(Al,X) phase) embedded in the nickel matrix. This composite structure provides both the thermal stability and mechanical strength required for high-temperature engine environments while maintaining the wire form factor needed for brush seal functionality

Inventive Principle:
Principle #40Composite materials

2Temperature

If superalloys with increased gamma-prime precipitate concentrations are used to withstand higher turbine temperatures, then thermal resistance is improved, but processing into thin wires becomes impractical or impossible without sacrificing thermal and mechanical properties

Engineering Contradiction:
Improvethermal resistanceVSAvoidprocessing into thin wires
Core Design Contradiction:
TemperatureVSEase of manufacture

Solution Approach 1:

The patent optimizes the gamma-prime precipitate concentration parameter to a specific range (at least 25 vol%, preferably at least 40 vol% but not exceeding practical processing limits). This parameter optimization balances thermal resistance requirements with manufacturability, enabling the superalloy to be processed into thin wires (sufficiently thin diameter for brush seal use) while maintaining the necessary thermal and mechanical properties

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent applies local quality by ensuring the gamma-prime precipitates are distributed throughout the superalloy matrix in a controlled manner, creating localized strengthening regions that provide thermal stability without compromising the overall ductility and processability of the wire material. The precipitate distribution is optimized to maintain wire formability while providing high-temperature strength

Inventive Principle:
Principle #3Local quality

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution provides a cost-effective brush seal that maintains thermal and mechanical resilience, suitable for long-term exposure to higher temperatures and pressures, by utilizing a comb-like structure and limited superalloy wires to enhance sealing performance.

Implementation Method 1

brush seal configuration using precipitation hardened nickel superalloys, including single crystal superalloys

Methodology Applied
Scientific EffectPrecipitation hardening: Precipitation Hardening

Data Source

PatentEP3239473B1High temperature seal and method
Publication Date: 2021.06.02 RTX CORP
  • EP3239473B1 patent drawingFigure 1
  • EP3239473B1 patent drawingFigure 2A
  • EP3239473B1 patent drawingFigure 2B

AI summary

An embodiment of a turbine assembly includes, among other possible things, a first component including a first component surface, a second component including a second component surface spaced apart from the first component surface, and a brush seal (100) disposed between the first component and the second component. The brush seal (100) includes, among other things, a first bristled region (104) extending in a first direction (108) from a backing plate (102), and sealingly engaging one of the first component surface and the second component surface. At least one of the backing plate (102) and the first bristled region (104) includes a nickel-based superalloy material having at least 40% of a Ni3(Al, X) precipitate phase, X being a metallic or refractory element other than Al.