Which of the following is NOT a purpose of immersion testing?

Immersion testing is a technique used in ultrasonic testing where the test specimen is submerged in a liquid, usually water or a suitable coupling medium. This method facilitates several key advantages in the ultrasonic testing process.

The first purpose is to reduce air bubbles, which can hinder the transmission of ultrasound waves. By immersing the specimen in a liquid, any air gaps are eliminated, allowing the sound waves to propagate more efficiently through the medium and into the test material.

Enhancing significant contrast is another important function of immersion testing. The use of a liquid medium can help to improve the visibility of echoes on the display, allowing for clearer interpretation of results and making it easier to identify flaws or discontinuities within the material.

Improving sound coupling is also a critical advantage. The liquid in which the specimen is immersed serves as an effective couplant, ensuring that ultrasonic waves travel with minimal loss into the test material, thus providing more reliable measurements and accurate detection of flaws.

In contrast, decreasing material thickness is not a purpose of immersion testing. The thickness of the material being tested is a physical characteristic of the specimen and is not altered by the immersion process itself. Therefore, the accurate identification of material thickness, as it would relate to evaluation and inspection, does not fall within the