Clad Plates Ultrasonic Inspectability
Clad sheets can be inspected by ultrasonic testing to detect bond defects and delaminations. The testing frequency must be adapted to the acoustic impedance differences between the materials.
Physical-Chemical Mechanism of Action
Ultrasonic waves are transmitted through the sheet and echo at interfaces. Acoustic impedance differences between the layers affect the reflection and transmission of the waves.
Metallurgical Relevance & Risks in Welding
Bonding defects and delaminations can occur due to missing or insufficient welding. These defects impair the mechanical strength of the sheet and can lead to cracks. Accurate ultrasonic testing can detect these flaws before use and prevent issues.
Shop Practice & Instructions
For a successful test, the ultrasonic frequency must be matched to the acoustic impedance difference between the layers. A frequency of 2-5 MHz is typical for clad plates of steel and aluminum. The test should be performed at least 10 mm below the surface to ensure no delaminations or bonding defects are missed.