We are independent & ad-supported. We may earn a commission for purchases made through our links.

Advertiser Disclosure

Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.

How We Make Money

We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently from our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What is Ultrasonic Testing?

By M. Rosario
Updated May 17, 2024
Our promise to you
About Mechanics is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At About Mechanics, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Ultrasonic testing is the use of high frequency sound to inspect materials. The sound frequency normally ranges from .5 MHz to 25 MHz, which is well above what a human can hear. High frequency sound is used because it is able to penetrate most materials without difficulty, which makes it possible to conduct non-destructive testing. It is commonly used to look for cracks, measure material depth, and check for corrosion and imperfections.

An ultrasonic test works by bouncing sound off of an object and interpreting the resulting echo. It passes through the material until the sound waves encounter an irregularity. The operators usually note this as a “discontinuity.” By analyzing the discontinuity, the operator can determine if there is a flaw in the material.

The thickness of materials such as metals, ceramics and plastics can be measured with ultrasonic testing. Ultrasonic thickness testing is mainly done by calculating the time it takes for sound to bounce off the bottom of the material. Different materials typically reflect sound at different rates. By measuring the change in the time it takes for the sound to be reflected, the operator is able to measure the thickness of each material in a multilayer surface.

There are several types of ultrasonic testing equipment, depending on the required application. The choice of equipment is generally dictated by the material’s temperature, thickness, geometry and phase reversal. Ultrasonic test equipment typically has three components: a transducer, a couplant and an imaging system. A technician operates the ultrasonic testing equipment by manually moving the probe across the surface of the object being tested and interpreting the resulting data.

A transducer or probe produces and receives sound. Normally, a transducer sends sound in either a straight beam or in an angle beam. Straight beam transducers are more widely used than angle beam transducers, which are often used for ultrasonic weld testing.

A couplant is applied to the surface being tested to act as a medium between the transducer and the surface. Its main purpose is to transmit sound to the surface. It also increases accuracy by preventing loss of sound waves. Couplants are often made of gel or paste. Water, however, is often used as a couplant when using an immersion transducer.

Data from the test can be read with an imaging system. The imaging system normally contains the controls and processor. In some portable equipment, the transducer is also integrated into the imaging system.

About Mechanics is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.

Discussion Comments

About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.

About Mechanics, in your inbox

Our latest articles, guides, and more, delivered daily.