Facts About Flaw Detection: Application of Eddy Current Flaw Detectors in Automobile Parts

Eddy current nondestructive testing technology is a comprehensive testing technology that measures and evaluates the physical and mechanical properties of an object's interior or surface, as well as various defects and other technical parameters, without damaging the tested object. Its application scope is becoming increasingly broad with the development of science and production.

Using Eddy Current Flaw Detectors for Nondestructive Testing of Automobiles

In the automotive manufacturing industry, the application of eddy current flaw detectors for nondestructive testing is very extensive. For example, key safety components such as automotive parts, brake drums, brake discs, axle journals, and steering knuckles, if their surfaces develop fine cracks or have internal defects, under the long-term action of alternating stress, the cracks will gradually extend from the surface inward or from the inside outward, thereby creating a safety hazard. Therefore, the aforementioned components must undergo a series of nondestructive tests using eddy current flaw detectors during the manufacturing process. Commonly used nondestructive testing methods for automotive components include radiographic testing, ultrasonic testing, electromagnetic eddy current testing, magnetic particle testing, and penetrant testing, also known as the "five major testing methods."

With the development of science and technology, these five common nondestructive testing methods are also continuously evolving, such as real-time X-ray imaging, automatic magnetic particle flaw detection systems, eddy current flaw detectors, magnetic flux leakage automatic detection systems, and the emergence of new penetrant materials. In addition, new methods have been added to nondestructive testing, such as acoustic emission, microwave, infrared, holography, and photoelastic display, which are referred to as the new five major testing methods. There are also new methods like electron paramagnetic resonance, atomic scale stress testing, electron diffraction, resonance scattering and absorption by recoil-free nuclei, laser-induced shock pulse, and positron annihilation, among others. Currently, there are nearly 50 methods included in the category of nondestructive testing.

Due to the complex geometry of automotive components, high equipment standards, complex materials, equipment diversity, and high precision requirements are essential. Additionally, automotive parts production is a large-scale industrial process with specific rhythm monitoring requirements, and only by reducing testing costs can the cost of car production be lowered, improving competitiveness in the domestic and international markets. With the development of the national economy, the automobile industry has become a pillar industry in our country. Therefore, nondestructive testing technology using eddy current flaw detectors for automotive parts has also garnered increased attention from both manufacturers and researchers.

Electromagnetic Eddy Current Flaw Detectors Are Developing Towards Digital Signal Processing and Imaging

Currently, in the detection of automotive parts, the most widely used nondestructive testing method is the electromagnetic eddy current testing method. It is the most frequently used method in both domestic and international eddy current testing, offering high efficiency and cost-effectiveness, enabling defect localization and quantification, and is widely applied in production inspections.

Due to the continuous development of computer technology and electronic devices, the digitized acquisition and analysis of electromagnetic eddy current testing signals, waveform recording and preservation, and the development of electromagnetic eddy current flaw detectors towards digital signal processing and imaging.

Therefore, the nondestructive testing methods of eddy current flaw detectors for automotive parts will increasingly develop towards intelligence, automation, and imaging with the continuous advancement of modern high technology, to meet the quality inspection and testing needs of components of the rapidly developing modern automotive manufacturing industry.