3D Grain Mapping for Turbine Component Boundary Inspection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Inspection of single crystal turbine components for secondary grains is labor-intensive and prone to errors due to reliance on human visual assessment, requiring highly trained inspectors.

Innovation Solution

An automated method and system using RGB light scanning and structured light to construct a three-dimensional model, overlaying RGB light scans on the model to identify grain boundaries by analyzing changes in color and contrast.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If human visual assessment is used to inspect grain boundaries, then inspection accuracy can be maintained with trained inspectors, but inspection time and labor costs increase significantly

Engineering Contradiction:
Improvegrain boundary detection accuracyVSAvoidinspection time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent replaces the mechanical visual inspection system with an automated optical scanning system. A light source illuminates the component surface while a camera captures images of the etched grain structure. Image processing algorithms automatically detect and map grain boundaries, eliminating the need for human inspectors to visually examine each component while maintaining detection accuracy and significantly reducing inspection time.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent creates a digital copy of the component surface through photographic imaging. The camera captures the etched surface appearance, and software processes these images to generate a grain boundary map. This digital representation allows automated analysis without requiring physical human inspection, thereby reducing time loss while preserving measurement precision.

Inventive Principle:
Principle #26Copying

2Productivity

If automated scanning is implemented to reduce inspection time, then productivity increases, but system complexity and initial costs increase

Engineering Contradiction:
Improveinspection throughputVSAvoidautomation system complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent employs a camera that serves multiple functions: capturing the component geometry, recording the etched surface appearance, and providing images for grain boundary detection. This multi-functional approach increases productivity through automation while minimizing the addition of separate complex subsystems, as the same imaging device performs multiple inspection tasks.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The system uses the component's own etched surface features to enable detection. The etching process creates optical contrasts at grain boundaries that the camera naturally captures without requiring additional markers, coatings, or complex sample preparation. This self-service approach allows automated inspection to proceed with minimal additional complexity beyond the basic imaging system.

Inventive Principle:
Principle #25Self-service

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

Enhances the speed and accuracy of grain mapping by reducing human error and improving inspection efficiency.

Implementation Method 1

The etchant generates a color and/or contrast based on orientation of the crystal structure and incoming light source

Methodology Applied
Scientific EffectOptical reflection and absorption: Reflection

Implementation Method 2

This can be accomplished by etching components in an appropriate etchant to reveal grain structure, such as Kallings etchant, AG-21 etchant containing nitric and hydrofluoric acid, or a ferric acid etchant followed by an anodic etch in phosphoric acid based etchant

Methodology Applied
Scientific EffectEtching:

Data Source

PatentEP4672141A1Method for automated grain mapping
Publication Date: 2025.12.31 RTX CORP
  • EP4672141A1 patent drawingFigure 1~4
  • EP4672141A1 patent drawingFigure 5
  • EP4672141A1 patent drawingFigure 6

AI summary

A method for grain mapping of a surface of a component includes the steps of constructing a model comprising a three-dimensional scanned model of the component; scanning the component with RGB light to obtain an RGB light scan; applying the RGB light scan to the three-dimensional scanned model of the component to produce a combined three-dimensional model of the component with an RGB light scan overlay on the three-dimensional model; and analyzing the combined three-dimensional model of the component with the RGB light scan overlay on the three-dimensional model to identify grain boundaries in the component.