Effect of microstructural elongation on backscattered field: Intensity measurement and multiple scattering estimation...

Area of Science:

• Materials Science
• Non-destructive Testing
• Ultrasonic Testing

Background:

• Microstructural features significantly influence material properties.
• Ultrasonic backscattered fields contain rich information about material microstructure.
• Characterizing microstructural anisotropy is vital for titanium alloy applications.

Purpose of the Study:

• To investigate the effect of microstructural elongation on ultrasonic backscattered fields.
• To develop and validate methods for determining macrozone elongation direction in titanium alloys.
• To compare the anisotropy of TA6V and Ti17 titanium alloys.

Main Methods:

• Utilized a phased array ultrasonic transducer on a rotative holder to record the array response matrix at multiple angles.
• Developed two methods based on anisotropic spatial coherence of the backscattered field.
• Method 1: Analyzed angular dependence of backscattered intensity.
• Method 2: Measured the proportion of single to multiple scattering using a simplified single scattering filter.

Main Results:

• TA6V exhibited significant macrozone elongation, while Ti17 showed equiaxial macrozones.
• Method 1 identified elongation direction by minimal backscattered intensity at specific probe angles.
• Method 2 determined elongation direction by minimal multiple scattering.
• Both titanium alloys displayed strong multiple scattering characteristics.
• Coherent backscattering cone measurements confirmed the determined elongation directions.

Conclusions:

• The study successfully demonstrated two novel ultrasonic methods for determining microstructural elongation direction in titanium alloys.
• The findings highlight the utility of analyzing ultrasonic backscattered fields for anisotropic material characterization.
• The developed techniques offer valuable tools for quality control and material assessment in titanium alloy manufacturing.