Total Focusing Method in Phased Array
Phased array total focusing method is an advanced ultrasonic signal processing technique that mathematically superimposes all transmitter-receiver combinations of an array to perfectly focus every point in the test volume. This enables precise detection of lack of fusion and cracks.
Physical-Chemical Mechanism of Action
The Phased-Array Total Focusing Method (TFM) uses an array of multiple ultrasonic transmitters and receivers. Through the phase-dependent transmission of signals, all transmitter-receiver combinations can be mathematically superimposed. This results in a focused sound field that perfectly penetrates every point of the test volume.
Metallurgical Relevance & Risks in Welding
TFM is particularly useful for the precise detection of flaws and cracks in complex geometries. It increases the resolution and sensitivity of ultrasonic testing, leading to improved quality assurance. However, there is a risk that incorrect settings or faulty signal transmission can lead to inaccurate results.
Workshop Practice & Action Instructions
To use TFM effectively, the following steps must be observed:
1. Array Calibration: Make sure all transmitters and receivers are correctly calibrated.
2. Phase Control: Adjust the phase shift of the signals to achieve perfect focusing.
3. Mathematical Superposition: Use specialized software for the mathematical superposition of transmitter-receiver combinations.
4. Interpretation of Results: Carefully analyze the ultrasonic images and compare them with reference data to identify flaws and cracks.