The inspection of anisotropic single-crystal components using a 2-D ultrasonic array

Area of Science:

• Materials Science
• Non-destructive Testing
• Mechanical Engineering

Background:

• Single-crystal metal alloys are crucial for jet engine components due to high-temperature mechanical strength.
• Current 2-D ultrasonic array inspections face challenges with single-crystal anisotropy, hindering defect detection.
• Elastic anisotropy in single crystals causes directional variations in ultrasonic wave propagation.

Purpose of the Study:

• To adapt ultrasonic imaging algorithms for anisotropic single-crystal materials.
• To enable accurate three-dimensional subsurface defect detection in single-crystal components.
• To develop and evaluate methods for determining crystallographic orientation using ultrasonic arrays.

Main Methods:

• A wave propagation model for anisotropic materials was employed to correct an ultrasonic imaging algorithm.
• The corrected algorithm was applied to a single-crystal test specimen.
• Crystallographic orientation measurement techniques using 2-D ultrasonic arrays were developed and assessed.

Main Results:

• The corrected ultrasonic imaging algorithm demonstrated applicability to single-crystal specimens.
• Knowledge of crystal orientation is essential for the corrected algorithm's success.
• Integrated methods for orientation measurement and defect inspection using ultrasonic arrays were evaluated.

Conclusions:

• The developed ultrasonic imaging approach can overcome anisotropy challenges in single-crystal materials.
• Simultaneous orientation measurement and defect inspection using 2-D ultrasonic arrays offer a practical solution for component integrity.
• This research advances non-destructive evaluation for critical single-crystal aerospace components.