Summary:Ultrasonic nonlinear analysis, as a non-destructive testing technique, is mainly used for risk assessment of microcracks, weak bonding, and fatigue strength in materials. Unlike conventional ultrasonic nonlinear analysis and harmonic measurement of nonlinear coefficients, this paper proposes a new method for intuitive imaging of internal microcracks in materials using ultrasonic phased array nonlinear imaging. By detecting AISI304 and AL7075 specimens and comparing them with traditional ultrasonic phased array linear imaging, it is found that this method can effectively improve the contrast noise ratio and help detect internal microcracks in materials. key word:Nonlinear ultrasonic phased array microcrack non-destructive testing 1. Research background1.1 Nonlinear Ultrasonic Harmonic Analysis Method1The conventional nonlinear ultrasonic harmonic analys...

Shaw.Din     Charles. Huang             TECLABIn recent years, China's high-speed rail technology has made rapid progress and has frequently won large orders in the international market. Under heavy loads, railway tracks are prone to fatigue and even cracking in stress concentration areas due to repeated rolling and trampling by trains over the years, as well as temperature changes. In recent years, corresponding rail inspection technologies and methods have also undergone innovative development: from hammer tapping sound detection decades ago to ultrasonic A-scan manual detection, and now to fully automatic ultrasonic high-speed flaw detection vehicle online detection, domestic rail integrity and health testing is also advancing with the times and flourishing. This article introduces various current ultrasonic orbit detection ...

The residual stress generated in the workpiece by mechanical processes can reduce the strength of the workpiece, resulting in process defects such as deformation and cracking; On the other hand, the natural release process may cause changes in the size of the workpiece or reduce its mechanical properties such as fatigue strength and stress corrosion. The measurement of residual stress is of great significance for ensuring the safety and reliability of workpieces.At present, there are two main methods for measuring residual stress: mechanical method and physical method. Mechanical methods such as drilling require the destruction of workpieces; Physical methods such as X-ray, magnetic measurement, and ultrasonic testing are all non-destructive testing methods that do not cause damage to the workpiece. Measurement of residual stress by X-ray diffractionAs a widely used techni...

Ding Xiashaw@teclab.cnRuitaike (China) Co., LtdSummary:This article introduces various non-contact detection methods based on laser ultrasound for evaluating the quality of chip packaging. By comparing with ultrasonic microscope, X-ray and scanning electron microscope, it was found that laser ultrasonic testing technology has a relatively higher detection possibility in the quality inspection of the second layer bonding; Compared with common time-domain or amplitude imaging methods, the resonance time-domain amplitude correlation coefficient method is easier to implement, can significantly improve detection speed, and has a relatively high detection rate. Finally, several potential non-destructive testing methods for chip packaging were proposed and preliminarily validated. keyword:Laser ultrasonic chip packaging inspection ultrasonic microscope Background:In the...

Ding Xia shaw * teclab.cn Ruitaike (China) Co., LtdSummary:Ultrasonic nonlinear analysis, as a non-destructive testing technique, is mainly used for risk assessment of microcracks, weak bonding, residual stress, and fatigue strength in materials. Unlike conventional ultrasound based on time-domain signal amplitude detection technology, nonlinear ultrasound detection technology is based on non-destructive evaluation of fundamental frequency and harmonic frequency intensity. This article uses an HPA high-power amplifier to excite the fundamental frequency probe with a Hanning window sine signal, and analyzes the nonlinear coefficients of rock samples by receiving the transmitted signal through a broadband harmonic probe. Verified the feasibility of the ultrasonic nonlinear research platform based on HPA high-power amplifier. key word:Nonlinear ultrasonic phased arra...

Ding Xia shaw * teclab.cn Ruitaike (China) Co., LtdSummary:This article introduces a non-contact detection method based on laser ultrasound for the detection and evaluation of residual stresses in materials. Laser ultrasound has the characteristics of numerical accuracy and deeper detection depth in residual stress detection. In addition, due to the advantages of non-contact, non-destructive, broadband, and high precision of laser ultrasound, it is easy to apply in harsh environments such as high temperature and high pressure, and can achieve rapid and real-time detection. It has a wide range of application scenarios in the field of non-destructive evaluation and testing. keyword:Laser ultrasonic residual stress detection Background:Residual stress refers to the internal stress that remains in equilibrium within an object without considering external forces or une...