Eddy current flaw detector is a comprehensive non-destructive testing technique used to determine and evaluate the physical and mechanical properties, defects, and other technical parameters of the inside or surface of objects without damaging them. Its application range is becoming increasingly wide with the development of science and production.
Eddy current flaw detector is widely used in the automotive manufacturing industry. Key safety components such as brake drums, brake discs, axle necks, and steering knuckles may develop cracks on their surfaces or internally, leading to safety hazards when subjected to long-term alternating stress. Therefore, these components must undergo a series of eddy current flaw detection tests during production.
The commonly used non-destructive 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, the five commonly used non-destructive testing methods are also constantly evolving, such as real-time X-ray imaging, automated magnetic particle testing and judging systems, eddy current flaw detection leaky magnetic automatic testing systems, and the advent of new penetration materials.
In addition, new methods such as acoustic emission, microwave, infrared, holographic photography, and photoelasticity are known as the "new five testing methods."
Other new methods include electron paramagnetic resonance, atomic-scale stress testing, electron diffraction, recoil-free nuclear resonance scattering and absorption, laser-induced shock wave pulse and positron annihilation. Currently, nearly 50 methods are included in the scope of non-destructive testing.
Due to the complex geometric shape and high equipment requirements of automotive components, as well as the complexity of materials used, diversified and high-precision equipment is required. In addition, the production of automotive components is a large-scale industrial production, which requires regular monitoring. Only by reducing testing costs can we reduce the cost of automotive production and improve its competitiveness in the market.
With the development of the national economy, the automotive industry has become a pillar industry in China. Therefore, the eddy current flaw detection technology for automotive components is increasingly receiving attention from manufacturers and researchers.
Currently, the most widely used non-destructive testing methods for automotive components are eddy current flaw detection and ultrasonic testing. The most widely used ultrasonic testing method is type A ultrasonic flaw detection, which uses type A ultrasound display and has the advantages of simple equipment and low cost. It can locate and quantify defects and is widely used in production inspection. However, it has the disadvantages of being non-intuitive, non-recordable, difficult to test, and affected by many human factors, which seriously affect the reliability of testing.
With the continuous development of computer technology and electronic devices, digital acquisition and analysis of eddy current flaw detector and ultrasonic signals have become possible, and waveforms can be recorded and saved. The eddy current flaw detection and ultrasonic testing positive digital signal processing and imaging directions are developing. Ultrasonic imaging technology is a remarkable new technology that provides intuitive and abundant information about the object's acoustic and mechanical properties, can evaluate the microstructure and related mechanical properties of solid materials, and detect microscopic and macroscopic discontinuities.
In summary, the eddy current flaw detector non-destructive testing method for automotive components will continue to evolve towards intelligent, automated, and image-based directions with the continuous progress of modern high-tech, in order to meet the needs of quality inspection and testing of modern automotive manufacturing industrial components.