Which factor is NOT influenced by the interfaces in phased array ultrasonic testing?

The duration of the testing process is not directly influenced by the interfaces in phased array ultrasonic testing. The interfaces between different materials can affect various aspects of the testing process, such as how sound waves propagate through the materials, which in turn can influence the angle of incidence and reflection coefficients.

In phased array ultrasonic testing, the type of materials being tested will dictate how the sound waves interact with those materials. Different materials have varying acoustic properties, which ultimately affects how sound waves are transmitted and reflected at the interfaces. Similarly, the angle of sound wave incidence is crucial because it determines the path of the sound waves and their reflection and refraction at material boundaries, directly influencing the effectiveness of the testing.

Lastly, reflection coefficients, which indicate how much of the sound energy is reflected back at the interface versus transmitted into the other material, are also dependent on the materials in question and their characteristics. However, the overall duration of the testing process is more dependent on the methodology, equipment setup, and experience of the operator rather than the physical interfaces between materials.