Ultrasonic examination (UT) is a type of Nondestructive Testing commonly used to find flaws in materials and to measure the thickness of objects. An inspection may be manual or automated and is an essential part of the modern manufacturing processes.

Most metals can be inspected, as well as plastics and aerospace composites. Lower frequency ultrasound (50 kHz to 500 kHz) also can be used to inspect less dense materials such as wood, concrete, and cement. When a piezoelectric crystal is driven by high-voltage electrical pulses, the crystal rings at its resonant frequency and produces short bursts of high-frequency vibrations. These sound wave trains generated by the ultrasonic transducer or search unit are transmitted into the material being tested. When the search unit is in direct contact with the test material, the technique is known as contact testing.

How UT Works

If flaws or discontinuities are present, an acoustic mismatch occurs, and some or all of the ultrasonic energy is reflected back to the search unit. The piezoelectric crystal in the search unit converts the reflected sound wave or "echo" back into electric pulses whose amplitudes are related to flaw characteristics and whose time of travel or time of flight through the material is proportional to the distance of the flaw from the entrance surface.

Ultrasonic pulses also are reflected from the back surface to the material, and this signal represents the total distance traveled. The pulse received from the back surface also can represent the width, length, or thickness of the material, depending on its orientations. Ultrasonic thickness testing measures the wall thickness of pipes and vessels by measuring the total distance traveled by the ultrasonic pulses, represented by the distance from the initial pulse or front surface to the back reflection from the back surface.

Ultrasonic flaws and thickness indications are frequently displayed on an instrument or computer display screen.

Ultrasonic Screen
Ultrasonic Testing Closeup
Ultrasonic Testing Screen
Ultrasonic Testing Equipment
Ultrasonic Testing Staff



Ultrasonic Paint Thickness Measurement is a specialized nondestructive testing (NDT) technique designed to accurately gauge the thickness of paint and coatings on various materials, including metal, plastic, and composite substrates. Utilizing high-frequency ultrasonic waves, this method provides immediate, precise results, enabling you to assess the quality and durability of protective coatings without damaging the surface. The process involves sending an ultrasonic pulse through the coating, measuring the time it takes for the pulse to bounce back, thus determining the coating’s thickness.

This technique is critical for industries where the quality of surface coatings directly impacts product performance and longevity, such as automotive, aerospace, and marine applications. Accurate paint thickness measurements ensure compliance with industry standards, optimize material usage, and can identify uneven or insufficient coating applications that could lead to corrosion or wear over time.

By integrating Ultrasonic Paint Thickness Measurement into your quality control process, you’re investing in a rapid, reliable, and non-invasive method for ensuring the highest standard of coating applications. This not only guarantees product durability but also reduces waste, ultimately contributing to both operational efficiency and environmental sustainability.


Bond testing is a nondestructive evaluation technique that assesses the integrity of bonds between different materials, such as laminates, composites, and metals. Various methods including pitch-catch, mechanical impedance analysis (MIA), resonance, and thru-transmission techniques are employed for this purpose. These techniques use ultrasonic waves or mechanical stress to evaluate the quality of bonds, and they are particularly important in industries like aerospace, automotive, and electronics for ensuring the reliability of critical components. Any anomalies in the test data, such as unexpected resonances or transmission characteristics, can indicate compromised bonds, allowing for targeted repairs or component rejection.