Ultrasonic Inspection Techniques Quiz

The angle of incidence at which the refracted angle of shear waves reaches 90 degrees. Beyond this angle, shear waves no longer propagate in the material.

Waves that travel along the surface of a material. They are generated when the incident angle exceeds the second critical angle.

Most angle beam inspections are performed with only shear waves present in the material. The incident angle is chosen to be between the first and second critical angles.

The angle at which the refracted angle of longitudinal waves reaches 90 degrees. Beyond this angle, longitudinal waves no longer propagate in the material.

A law used to calculate the angle of incidence needed to produce a specific refracted angle in a material.

The frequency of the ultrasonic waves used in an inspection. Higher frequencies provide greater sensitivity to small flaws but have less penetrating power.

A range of factors affecting the quality of an ultrasonic inspection, including the inspection equipment, transducer, coupling medium, and the material being tested.

Scanning equipment utilizes devices like two-axis scanners and multi-axis gantry systems to cover inspection areas comprehensively. This allows for detailed scans of intricate parts at resolutions beyond manual inspection.

Two-axis scanners can be manually adjusted or programmed for automated movement. These scanners allow for precise inspection of surfaces.

Large gantry systems, often used for immersion or

Older ultrasonic instruments have mechanical controls like rotary knobs for fine adjustments. These knobs allow for precise control of the waveform.

Newer instruments use push buttons or membrane keypads for control. These buttons provide access to various settings and adjustments.

Menu-driven instruments use a single rotary knob for making adjustments after selection from a menu.

Ultrasonic instruments can display waveforms on various screens like CRT, LCD, or EL. These displays visualize ultrasonic signals.

CRT screens can be damaged if exposed to high intensity for prolonged periods. Therefore, it's essential to control screen brightness.

Adjusting the horizontal and vertical scales on the waveform display allows for precise positioning of the baseline.

Used for calibrating angle beam metal path distances, measuring beam exit point and refracted angle of angle beam transducers.

A standard reference block used in NDT for calibration and measurements of angle beam transducers. It helps determine beam exit point, refracted angle, and metal path distances.

A smaller and lighter version of the Type 2 IIW block, used for similar purposes including angle beam transducer calibration.

Used to develop distance-amplitude correction (DAC) curves in ultrasonic testing.

A specific block used in NDT to determine the sensitivity to surface-breaking flaws like cracks. They are used for calibrating the sensitivity of the testing equipment.

The ability of an inspection system to identify small defects.

Sensitivity is typically increased by using a higher frequency transducer, but this reduces penetrating power.

The ability of an inspection system to distinguish separate signals from interfaces close together.

Resolution is influenced by the damping or backing material of the transducer, with low damping leading to a wider front surface signal and poorer resolution.

Resolution is generally better at higher frequencies.

Transducers can be round or rectangular in shape, with sizes ranging from 1/8-inch diameter and smaller.

Dual transducers are used primarily in applications where good near-surface resolution is required. They consist of two transducer elements with a delay line to mitigate interference from the initial pulse.

Dual transducers are used in both thickness measurements & angle beam inspections, offering improved near-surface resolution compared to single transducers.

A delay line is used in dual transducers to avoid interference from the initial pulse, allowing clearer near-surface observations.

Dual transducers are commonly used in ultrasonic thickness measurement instruments, offering improved accuracy and near-surface resolution.

Couplant material is vital for transmitting sound waves between the transducer and test piece, ensuring accurate readings.

A shoe is a specifically designed block used to create an even contact between the transducer and curved surfaces during ultrasonic inspection.

Shoes are often made from acrylic plastic, offering flexibility and adaptability to various test part shapes.

When a shoe is made of the same material as the test part, sound waves travel directly without bending.

The shoe's curvature must align with the test part's curvature to ensure accurate sound wave transmission.

Sandpaper can be used to adjust minor deviations in the shoe's curvature against the test part.

Major reshaping of an ultrasonic shoe is best done in a machine shop due to the precision required.

When using plastic shoes on curved surfaces, unwanted sound wave reflections can occur, especially with tight curves.

Slots cut into the shoe can help mitigate unwanted sound wave reflections by directing them away from the test area.

For large inspection angles and curved surfaces, it's better to avoid a tight shoe fit to minimize unwanted wave interference.