In the present study, the effect of cerium content in the range of 0~0.0676% on oxygen and sulfur content, as well as the quantity, size, distribution, and type of inclusions in C104Cr saw wire steel, were investigated using thermodynamic analysis, metallographic examination, SEM-EDS, and component analysis. The results showed that conducting a vacuum carbon pre-deoxidization process is helpful in preventing the formation of Ce₂O₃ inclusions in a smelting experiment, and cerium has a beneficial effect in terms of modifying inclusions. When the content of cerium in steel is 0.0136% or 0.0277%, the main inclusions in the steel are Ce₂O₂S and CeS, and when the content of cerium is 0.0389% or above, the inclusions in the steel are Ce₂O₂S, CeS, Ce–S–O–P(As), Ce–O–P, and Ce–P(As). The calculation of the segregation model showed that the precipitation of CeP and CeAs in steel takes place at the end of solidification. According to the element mapping distribution diagram of Ce–S–O–P(As) and the layered Ce–O–P inclusions found in steel with high cerium content, two possible mechanisms for the formation of Ce₂O₃ inclusions distributed in the outer layer of cerium composite inclusions are proposed. The first mechanism suggests that Ce₂O₃ inclusions are generated from the combination of [Ce] and [O] directly, and the second suggests that Ce₂O₃ is the product of an oxidization reaction after the formation of CeP.

To clarify the effect of sulfur on inclusions and mechanical properties of Ce-Mg treated resulfurized SCr420H steel. Laboratory experiments were conducted to prepare steels with sulfur contents as 0.01%, 0.06%, and 0.132%. Inclusion evolution in liquid steel, MnS precipitation during solidification, and tensile test results of steel after quenching and tempering were investigated. The results showed that due to the limitation of mass transfer in molten steel, composite inclusion that Ce-O-S wrapped by Ce-Ca-Mg-Al-Si-O, which was named transition state inclusions, can form quickly after adding Ce-Mg lump to the molten steel. As the homogenization of molten steel, the difference of sulfur content in steel can lead to the transition state inclusions transformed into different inclusions. With the increase of sulfur content, the quantity of MnS increased significantly, and the morphology of MnS transformed from “stick” to “dendritic + fishbone”, and then to “fishbone”. Tensile test results and fracture analysis indicate that the decline of inclusion spacing as the increase of sulfur content leads to a shorter physical path of crack propagation in steel. Therefore, the increase of sulfur content can bring about a decrease in the strength and plasticity of the steel. From the perspective of inclusion control, making the MnS inclusion precipitate more dispersive and increasing the distance between inclusions can be considered as a method for preventing the decline of mechanical properties in steel with high sulfur content.

Steel tire cord and steel saw wire represent typical precision pearlitic steel wire rods of wire products; it is a very important solar energy material with a diameter about 50 μm. This paper mainly discusses the research progress of the wire rod drawing process, and its main contents are as follows: First section—the control of the wire rod surface quality is summarized, including the thickness of the surface decarburization layer, the phase composition and thickness of the surface iron oxide scale, and the removal of surface iron oxide scale. Then, the research progress of the wire rod water bath treatment process during sorbitization is summarized. In addition, the development of brass plating technology for steel wire is summarized, including copper plating technology, coating phase composition, etc. Furthermore, the development of steel wire drawing methods is summarized. Finally, the development of the dies used in steel wire drawings is summarized.

The effects of the Al₂O₃ content and basicity of CaO–SiO₂–Al₂O₃–10 wt.% MgO refining slag on inclusions removal in 55SiCr spring steel were investigated. The viscosity of slag was studied using a viscometer, while the microstructure investigation involved using a water-quenching furnace and a Fourier-transform infrared spectrometer. The influence mechanism of the slag adjustment on inclusions was explored through thermodynamic calculations and kinetic analysis. The results indicated that the viscosity of the molten slag increased gradually with the content of Al₂O₃ increasing due to it increasing the degree of polymerization of the slag network structure, especially the [AlO₄]⁵⁻ and [Si-O-Si] structures. In contrast, the viscosity of molten slag experienced the opposite pattern, with the basicity of molten slag increasing. This was due to the fact that Ca²⁺ can significantly reduce the degree of polymerization of a slag network structure, especially the percentages of the [SiO₄]⁴⁻, [AlO₄]⁵⁻ and [Si-O-Si] network structures. Finally, the changes in physical properties and structure of slag significantly affected the removal effect of the inclusions in molten steel. As a result, the number, size distribution, composition distribution and morphology of the inclusions displayed significant changes when the content of Al₂O₃ increased from 3 wt.% to 12 wt.% and the basicity of the slag gradually increased from 0.5 to 1.2.

Tyre cord wires and steel saw wires represent typical precision pearlitic steel wire rods. Reducing the rate of wire breaking is one of the most concerning problems in metallurgy. This paper surveys the technical progress in the control of inclusions and central segregation in tyre cord steel wires and saw wire steel in the last 20 years, including the control of the [Al]s content in steel, selection of better refractories, deletion of the VD process, developing of new kinds of refining slag system, optimize the structure of tundish, control of Ti-containing inclusions, feeding steel trip into a mould, electromagnetic stirring technology, soft reduction technology at the solidification end of continuous casting slab, and the control of billet size. Finally, the unresolved issues that should be studied in the next 10 years have been formulated.