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Bearing is one of the key components widely used in mechanical equipment. Due to overload, fatigue, wear, corrosion and other reasons, bearings are easily damaged during machine operation. Therefore, the monitoring and analysis of the bearing state is very important. It can find the early weak fault of the bearing and prevent the loss caused by the fault. This paper proposes a long-term and short-term network combining the lightweight convolutional block attention module (CBAM-LSTM). In the field of bearing fault detection, the experimental results show that the CBAM-LSTM method can accurately identify a variety of mechanical bearing faults with an accuracy of 99,13 7 %.

High nitrogen steel has been widely explored and developed due to their unique properties. At present, most of the references on high nitrogen steel powders prepared via gas atomization mainly focus on their initial and secondary crushing. The research on the enhanced crushing process caused by the “nitrogen escape” inside the high nitrogen molten steel is rare. In this paper, the enhanced crushing process of high nitrogen steel molten droplet is investigated based on the theoretical calculation and numerical simulation, which reveals the enhanced crushing mechanism of nitrogen-containing droplets in the process of preparing high nitrogen steel powders by atomization method.

Aiming at the large weight of automobile steel solid shaft, this paper innovates aluminum alloy hollow shaft. The rolling process of automobile hollow shaft was simulated by using the short process flexible precision forming process and the Finite Element Method (FEM). The variation of the shape and inner hole of the rolled piece, the roundness of the outer surface and the wall thickness during the rolling process were analyzed. The numerical results verify the feasibility of rolling aluminum alloy automobile hollow shaft by this process, and provide a theoretical basis for forming aluminum alloy automobile hollow shaft in China.

In this paper, SiCp/TC11 titanium matrix composites were prepared by selective laser melting. The influence of laser process parameters on the forming quality of composites was studied by control variable method. The results show that the process parameters have a significant effect on the forming quality of the composite material. The laser power has the greatest influence on the density, followed by the scanning spacing, and the scanning speed has a relatively small influence. When the laser power is 160 ~ 180 W, the scanning speed is 1 000 ~ 1 200 mm/s, and the scanning spacing is 0,1 mm, the forming quality of the sample is better.

As a typical cutting tool with good performance and high processing efficiency, metallurgical saw blades are widely used in various industries, but surface defects are inevitably generated in the manufacturing process. To solve this problem, this paper proposes a YOLOv5-based surface defect detection model for product quality, which can distinguish three common metallurgical sawblade surface defects with mAP value of 96,1 % in each defect category detection of metallurgical sawblades and detection time of 139,8 ms per image.

The paper shows the results of studies in searching for a binder for briquetting finely dispersed dust (FDD) of ferroalloy production of the Kazakhstan content. The fractional composition and shape of FDD particles were studied. Liquid glass and caustic soda were used as a binder. The research results showed the possibility of using liquid glass as a binder. Experimental briquettes have sufficiently high compressive strength and drop strength, which implies the possibility of their transportation and loading.

In this paper, in order to achieve the resource utilization of metallurgical industry waste, the cracking resistance of magnesium oxysulfate cement coatings using granulated blast furnace slag powder and iron tailings powder as fillers was studied, x-ray Diffraction (XRD) and scanning electron microscope (SEM) were used to characterize the hydration products. The results show that an appropriate amount of slag powder and iron tailings powder can make the internal structure of the coating more compact, the surface smooth and effectively reduce the generation of cracks.

This paper presents the tribological properties of diamond-like-carbon coatings (DLC) doped with tungsten. The hardness of the DLC coating was determined using a micro-hardness tester. Friction tests were carried out on a tribometer in rotational motion in a 100Cr6 steel ball-disk association with a-C-H:W tungsten doped hydrogenated DLC coating. Tests were carried out with loads of 10 N, 25 N and 50 N under technically dry friction conditions. Using a scanning electron microscopy (SEM), the surface morphology was observed, and with a confocal microscope, the geometric structure of the surface was observed before and after the friction tests. The wetting angle of the samples was examined on an optical tensiometer for distilled water and diiodomethane. The results indicated that DLC coatings of the a-C:H:W type obtained by the PVD technique can be used in unlubricated high-load tribological systems.

This paper, the adaptive fuzzy control problem for finite-time command filtering is studied at the twin roll inclined casting system. An explosion of complexity caused by a differential surge can be avoided by constructing adaptive fuzzy controller combined with command filtering and backstepping schemes. The designed adaptive fuzzy controller ensures simultaneously the stability and tracking performance of the closed-loop system in a limited time, and the tracking error converges in a small neighborhood of the origin. Eventually, a simulation example is given to verify the effectiveness of the proposed scheme.

In this paper, the transient temperature field and thermal stress of the slagging-off robot arm were analyzed by finite element method, the temperature distribution and change of the robot arm in one working cycle were determined, and the thermal stress and thermal deformation of the slag-scraping plate after the skimming was completed were solved. The results show that the temperature of the equipment in the slagging-off process can reach 206 °C, and the heat can be transferred to the position of 200mm, which will not affect the key parts in the manipulator. Due to the direct contact with molten iron, the heat stress and deformation of the slag-scraping plate are large, which may result in the high melt loss rate of the slag-scraping plate.