As the core component of the fusion reactor device, the weld bevel of the vacuum chamber requires full weld penetration, and the welding quality has strict requirements. In this paper, phased array ultrasonic inspection was used to control the quality of T-shaped welds in the vacuum chamber of a fusion reactor. However, the coarse crystalline organization of the weld and the complex structure of the vacuum chamber brought challenges to the phased array ultrasonic inspection. In this paper, the simulation calculation of the probe focus and focal column size was performed by CIVA software, and the results provided reference for the design of the inspection scheme, and then the full detection of defects was achieved by using the inspection scheme of fan sweeping excited by a double-sided array probe on the side of the web, and linear sweeping with an angle perpendicular to the fusion line excited by a line array probe on the outer side of the wing plate to inspect the demonstration block with typical weld defects. The inspection program can provide guidance for the inspection of T-welds in practical applications.

High-pressure hydrogen storage cylinders are predominantly fabricated utilizing the fully wrapping methodology with carbon fibers, wherein the wrapping layers typically bear the majority of the internal pressure loads. Any incidence of damage within these layers poses a formidable threat to safety. This paper focused on the multi-scale industrial computed tomography detection of defects in the wrapping layer of hydrogen storage cylinder and carbon fiber wrapping layer specimen, using the principle of geometric magnification imaging in industrial computed tomography. A classification scheme for delamination defects within the wrapping layers was devised according to their respective thicknesses, followed by an in-depth analysis aimed at elucidating the underlying causes for the manifestation of such diverse defect types. The microstructure of carbon fiber wrapping layer specimen was characterized through the application of optical microscope and scanning electron microscope techniques. Thereafter, the accuracy of industrial computed tomography in qualitatively deciphering delamination defects, quantitatively determining thickness, and discerning the wrapping methodologies of wrapping layers was rigorously substantiated.

Based on the sensitive characteristics of nitrogen-vacancy (NV) color center to magnetic field, the diamond quantum sensor containing a concentration of 1-2 ppm NV color center was the core, and the quantum spin of the NV color center excited by microwave resonance frequency sweep was the foundation, and the NV color center was excited by the optimized confocal optical path to collect the reflected optical signal containing magnetic field information for signal collection, and the control acquisition module composed of three boards was used to filter and visualize the signal for signal processing, and a quantum precision measurement system was built. The quantum precision measurement system was used to detect metal cracks at a depth of 0.1 mm-1 mm and a lifting value of 5 mm-15 mm. The experimental results showed that the sensitivity of the system was 6 nT · $\sqrt{Hz}$^-1, the minimum depth of 0.1 mm and metal crack detection with a maximum lift value of 15 mm can be achieved, providing a new detection method for metal crack industrial detection.

The structural shape of selective laser melting (SLM) parts is complex. Conventional radiographic testing techniques are prone to blind spots in the detection of structurally complex parts.Industrial computerized tomography (CT) technology can achieve overall inspection of parts, and there is no blind spot for complex parts. At present, the design of industrial CT reference blocks lacks relevant experimental verification basis. Therefore, aiming at the representative problem of reference blocks, this paper carried out a study on the influence of defect forms, different locations of defects of the same size, cylindrical roughness, and the forming method on the detection results of industrial CT. The research results indicated that through hole defects were easier to detect than blind holes. The different locations of defects of the same size had no obvious influence on the detection of cavity defects, but the closer the defect was to the center, the greater the impact of circular artifacts. The surface roughness of the test block and the forming method of the test block matrix had no obvious influence on the detection of cavity defects.

In this paper, the coverage area of metal surface cracks was detected based on C-scan mode by using flexible Koch fractal eddy current sensor and traditional flexible circular parting eddy current sensor. The experimental results showed that cracks with a length greater than or equal to 3 mm can be effectively identified by C-scan. Among them, compared with the traditional flexible circular fractal eddy current sensor, the signal attenuation detected by the flexible Koch type eddy current sensor was small, and the phenomenon of missed detection was not easy to occur, and the detection of small cracks was particularly obvious.

At present, the industrial robot is used as the executive mechanism of the X-ray inspection system for the welding seam of the rocket tank, which usually follows the “teach-reproduce” trajectory movement and thus cannot adapt to the flexible and intelligent production line with small batch and variety. In this paper, servo mechanism, image processing technology and intelligent robot were combined, and the image-based visual servo control (IBVS) method was used to feed back the current image feature information, which was compared with the expected image feature to form the image feature deviation. The obtained feature error was based on SSA-BP control method, which was used to compensate the weld position error in the process of detecting the welding seam of rocket tank, so as to improve the working accuracy of the X-ray inspection system. Finally, the experiment showed that this method had good adaptability and robustness.

Coercive force testing is a nondestructive testing technique for detecting stress, which utilizes the relationship between coercive force and stress to accurately evaluate the stress state inside a material. Based on the theory of force magnetic coupling, the relationship between the coercive force and stress at different positions of 12Cr1MoVG specimens, 12Cr1MoVG welded specimens of the same type of steels, and 12Cr1MoVG/P91 welded specimens of different types of steels under different magnetization directions was studied. The results showed that the coercive force which direction of magnetization parallels to the direction of stress decreased first and then increased with the increase of stress. The coercive force which the direction of magnetization perpendicular to the direction of stress increased with the increase of stress. During the stretching process, the stress of the 12Cr1MoVG welded specimens of the same type of steels was concentrated in the base metal zone and heat affected zone. The stress of the 12Cr1MoVG/P91 welded specimens of different types of steels was concentrated in the 12Cr1MoVG base metal zone and its heat affected zone. The research results provided theoretical basis for the detection of coercive force in ferromagnetic materials.

A nondestructive testing technology based on weak magnetic principle was proposed to address the problem that existing nondestructive testing techniques were unable to meet the requirements of detecting multiple types of defects in wind turbine gears. Using the proposed method, the experiments were designed to detect two types of 17Cr2Ni2Mo steel samples with different defects, detection data were collected, signal processing and analysis were performed, and the results with industrial CT and Barkhausen noise detection were compared finally. The experimental results showed that weak magnetic detection technology was more sensitive to surface and internal crack defects of gears, had good recognition for grinding burns of gears, accurate positioning, and the results after signal processing were more-intuitive and clear. This method has the potential for application in nondestructive testing of wind turbine gears.