Which nondestructive testing method is suitable for inspecting metals, plastics, and ceramics for defects?

The correct answer is indeed ultrasonic inspection. This method utilizes high-frequency sound waves to detect internal and external flaws in materials such as metals, plastics, and ceramics. One of the advantages of ultrasonic inspection is its ability to provide precise measurements of material thickness and detect hidden imperfections that may not be visible through other testing methods.

Ultrasonic inspection works by transmitting sound waves into the material being examined. When these waves encounter a defect, they are reflected back to the detector, allowing the operator to determine the size, shape, and location of the defect. This method is not only effective for detecting various types of flaws, including cracks and voids, but it also offers the capability to inspect components that may be difficult to assess using other techniques, such as those with complex geometries.

In comparison, while visual inspection can identify surface defects, it is limited to what is visible and cannot detect subsurface issues. Radiographic inspection is excellent for seeing internal structures and defects, particularly in thick materials, but it is less effective with certain plastics and ceramics due to their transparency to the radiation used. Liquid penetrant inspection is useful for detecting surface-breaking defects, but it is unsuitable for internal detection and does not work well with porous materials like certain ceramics. Thus, ultrasonic