Shaw.Din        shaw@teclab.cn       TECLABSummary:The modulus value of materials is one of the important physical parameters for characterizing the mechanical properties of engineering materials. Static stretching method is currently the mainstream technical means. This method has a large load and slow loading due to stretching, resulting in relaxation strain. The size and loading speed of the load will affect the measurement accuracy. The conventional suspension resonance dynamic method forces the sample to vibrate by loading a small alternating stress, measures the natural frequency, calculates the modulus, and improves accuracy and measurement speed. The new resonance iterative calculation method introduced in this article calculates the theoretical resonance frequency through finite element analysis after obtaining the natu...

 Ding Xia TECLAB shaw@teclab.cnabstract：With the widespread application of fiber-reinforced composite components in the production field, especially in the automotive and aerospace industries, new challenges have been posed to non-contact non-destructive testing technology due to the demand for quality control. Ultrasonic testing, as a flexible and reliable non-destructive testing technique, has been widely used for defects such as internal delamination, cracks, and voids in materials. This article introduces a new non-contact non-destructive testing device based on laser excited ultrasound and using a broadband air coupled photoacoustic sensor for reception. The device can achieve non-contact detection of bilateral transmission and one transmitter and one receiver on the same side. It is a relatively economical and practical new non-destructive testing technolog...

The Young's modulus, shear modulus, bulk modulus, and Poisson's ratio of a material describe its basic mechanical properties, which are crucial for material manufacturers and researchers. The search for a simple and accurate technical means to measure the modulus of materials has always been a topic of interest for condensed matter physicists, engineers, and materials scientists. After verifying various methods and technical means such as RUS, IE, NI, 4PB, the advantages and disadvantages of each technology gradually became clear. Traditional tensile and compression tests for measuring elastic modulus cannot meet certain high-precision measurement requirements. TECLAB provides corresponding solutions based on the characteristics of the tested material:Resonant Ultrasound Spectrometer /RUSpec The ultrasonic resonance spectrum analysis method obtains the el...

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...