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Two heats of steel are melted using a vacuum induction furnace in the laboratory, with one heat undergoing magnesium treatment and the other being subjected to a combined magnesium–calcium treatment. The precipitation and agglomeration behaviors of inclusions of these two steel samples are observed using a high‐temperature confocal laser scanning microscopy. MnS precipitates form around oxide cores and undergo rapid growth during the solidification process of molten steel, and these MnS precipitates with oxide cores react with the cores, resulting in the transformation of the MnS into complex sulfides. In comparison with Al2O3 inclusions, MgO·Al2O3 inclusions have a lower critical velocity (Vc), making them more susceptible to being engulfed by the solid–liquid interface. As the size of colliding inclusions increases, the coalescence–collision frequency (E0) initially decreases until it reaches a minimum value. After that, with further size increments, the frequency starts to increase. During the inclusions growth process through collision, there is a distinct zone where coalescence–collision frequency is low. Inclusions that reach this zone struggle to grow further due to reduced collision coalescence, consequently leading to a predominance of inclusions with diameters in this zone. [ABSTRACT FROM AUTHOR]

The removal of inclusion particles is an important function of tundish metallurgy. During ladle change, the liquid level fluctuation around the ladle shroud is severe, which may affect the effectiveness of inclusion removal. In the present study, the fluid flow characteristics and inclusion‐removal behavior in the tundish during ladle change are investigated by numerical simulation method. And the effectiveness of flow control devices on the flow characteristics of molten steel is evaluated. It is found that the escape rate of inclusion particles during ladle change is ordered as emptying process < steady process < filling process. The proper combination of weir, dam, and turbulence inhibitor can optimize the conditions for the floating and removal of inclusion particles to the greatest extent. In the tundish with weir and dam, the escape rates of inclusion particles with sizes of 10, 50, and 100 μm throughout the entire ladle change period are respectively reduced by 9.8%, 1.6%, and 1.4%, compared to not using flow control devices. With a combination of weir, dam, and turbulence inhibitor, the escape rates of the three types of inclusion particles are reduced by 24.7%, 9.9%, and 1.2%, respectively. [ABSTRACT FROM AUTHOR]

Microwave imaging is a highly promising modality for the early detection of breast cancer. A multitude of image reconstruction algorithms have been devised. Previous methods utilized the coherence factor (CF) to enhance image quality. However, CF‐based methods often oversuppress the desired signals and introduce image artifacts when the signal‐to‐noise ratio is low. This study introduces a scaled coherence factor‐based delay multiply and sum (DMAS) Beamforming technique to achieve good noise suppression while maintaining robustness. The performance of this method was evaluated using datasets derived from an experimental breast phantom. The results show that the proposed method achieves improvements of signal‐to‐clutter ratio by 26%, signal‐to‐mean ratio by 7%, full‐width at half‐maximum by 8%, and localization error by 51% compared to the CF‐DMAS method. The suggested microwave imaging approach for breast cancer detection provides high resolution, contrast, and localization accuracy along with low computational complexity. [ABSTRACT FROM AUTHOR]

The morphology, distribution, and entrapped inclusions of bubbles in thick slab of X70 pipeline steels were investigated by peeling layer.The results show that the diameters of 94%bubbles in thick slab are less than 200μm;the bubbles and the entrapped inclusions are common in 8 mm depth from the slab surface, but the defects are hardly found as peeling deeper into the middle of slab, only a small number of defects are shown, presenting a random distribution in this area;the main morphology of bubbles existing in slab are single bubbles and twin bubbles, the calabash bubbles and petal bubbles are also found;the inclusions are mainly in four existent forms:oxides, aggregation in clusters, bubbles in clusters, and ash inclusions.