Journal of Iron and Steel Research International最新文献

{"title":"Low-temperature deNOx performance and mechanism: a novel FeVO4/CeO2 catalyst for iron ore sintering flue gas","authors":"Long Ding, He-xi Zhao, Ke Cheng, Li-xin Qian, Peng-yu Qi, Qi Shi, Hong-ming Long","doi":"10.1007/s42243-024-01203-8","DOIUrl":"https://doi.org/10.1007/s42243-024-01203-8","url":null,"abstract":"<p>Developing deNO_<i>x</i> catalysts with lower activity temperatures range significantly reduces NH₃ selective catalytic reduction (SCR) operating costs for low-temperature industrial flue gases. Herein, a novel FeVO₄/CeO₂ catalyst with great low-temperature NH₃-SCR and nitrogen selectivity was synthesized using a dipping method. Characterization techniques such as X-ray diffraction, Raman spectroscopy, specific surface and porosity analysis, H₂ temperature-programmed reduction, NH₃ temperature-programmed desorption, X-ray photoelectron spectroscopy, and the in situ diffused reflectance infrared Fourier transform spectroscopy were used to investigate the catalytic mechanism. An appropriate addition for FeVO₄ in the catalyst was 5 wt.% from the results, and the active substance content reached the maximum dispersal capacity of the carrier. The NO_<i>x</i> conversion exceeded 90%, and the nitrogen selectivity was more than 98% over this catalyst at 200–350 °C. The activity was kept at 88% after 7.5 h of reaction at 200 °C for 7.5 h in 35 mg m⁻³ SO₂ gas. The remarkable deNO_<i>x</i> activity, nitrogen selectivity, and sulphur resistance performances are attributed to the low redox temperature, the abundance of medium-strong acid and strong acid sites, the sufficient adsorbed oxygen, and the superior Fe²⁺ content on the surface. The Langmuir–Hinshelwood mechanism was observed on the FeVO₄/CeO₂ catalyst in the NH₃ selective catalytic reduction of NO_<i>x</i>.</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"2 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effects of Mg–Ca treatment and Ca treatment on impact toughness and morphology of sulfides in 45MnVS non-quenched and tempered steel","authors":"Tian-yin Zhan, Jun Tian, Xiang-long Li, Li-juan Su, Dong Hou, Tian-peng Qu, De-yong Wang","doi":"10.1007/s42243-024-01215-4","DOIUrl":"https://doi.org/10.1007/s42243-024-01215-4","url":null,"abstract":"<p>An industrial experiment was conducted at a certain steel plant in China to compare and analyze the effects of Ca treatment and Mg–Ca treatment on inclusions in 45MnVS non-quenched and tempered steel. Through scanning electron microscopy-energy dispersive scanning analysis of the morphology and composition of inclusions, as well as Aspex quantitative analysis of their quantity, type and size, the formation mechanism of MnS–oxide (MnS inclusions with oxide cores) was intensively studied. The influence of sulfide morphology on the impact properties of steel was also analyzed. The results show that the quantity percentage of spindle-shaped sulfides in Ca-treated steel is 19.99%, and that in Mg–Ca-treated steel is 35.38%. Compared with Ca-treated steel, there are more MnS–oxide inclusions in Mg–Ca-treated steel. Controlling the content of Ca and Mg in the oxide core of MnS–oxide inclusion above 10 wt.% and the area ratio below 5 would contribute to the formation of spindle-shaped inclusions after rolling. The mismatch between MnS and oxides decreases with the increase in MgO content in the oxides, which is beneficial to nucleation and precipitation of MnS with this type of oxides as the core. Under the same deformation conditions, the size of sulfide does not affect its aspect ratio. Under the experimental conditions, the inclusion containing a certain amount of MgO can enhance its sulfur capacity, facilitating the formation of composite sulfides. The transverse impact energy of Ca-treated steel is 25.785 J, and that of Mg–Ca-treated steel is 32.119 J. Compared with the traditional Ca-treatment, Mg–Ca treatment can increase the number of spindle-shaped sulfides in the steel, thereby improving the transverse impact toughness of the steel and reducing the anisotropy of the mechanical properties of the material.</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"60 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrosion mechanism of Zn–Al–Mg-coated steel in simulated polluted marine atmosphere","authors":"Pei-dong Ning, Li-yuan Xiao, Jin Wang, Qian-qian Liu, Kui Xiao","doi":"10.1007/s42243-024-01210-9","DOIUrl":"https://doi.org/10.1007/s42243-024-01210-9","url":null,"abstract":"<p>The corrosion behaviour of zinc–aluminium–magnesium-coated steel in a simulated polluted marine atmospheric environment was investigated. Therefore, an indoor ageing acceleration test was carefully designed by simulating a polluted marine environment. The objective was to in-depth investigate the corrosion mechanism of Zn–Al–Mg-coated steel exposed to a simulated polluted marine environment. The experiments were carried out by scanning electron microscopy for micro-morphological characterization, X-ray diffraction, electrochemical impedance spectroscopy and electrodynamic polarization curves for the aged samples. The analysis of the results obtained after an indoor accelerated ageing test shows that Zn–Al–Mg coatings generate insoluble Zn₅Cl₂(OH)₈·H₂O and Zn₄SO₄(OH)₆ during the corrosion process, which hinders the diffusion of corrosive substances into the substrate, and the insoluble substances are structurally dense and thus inhibit further corrosion. Therefore, this effectively inhibits the occurrence of further corrosion, and thus, Zn–Al–Mg coating can significantly extend the service life of Zn–Al–Mg-coated steel.</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"126 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of destructive effect of Zn on carbon brick and way of Zn into carbon brick","authors":"Peng-bo Liu, Shu-sen Cheng, Yu-qing Xue, Xiao-man Cheng, Zhao Liu","doi":"10.1007/s42243-024-01178-6","DOIUrl":"https://doi.org/10.1007/s42243-024-01178-6","url":null,"abstract":"<p>The service life of a blast furnace depends largely on the degree of damage to the carbon brick in the hearth. Carbon brick and ramming material in the hearth of a 1780 m³ blast furnace after shutdown were sampled and investigated. It was found that the substances in the cracks of the carbon brick near and above the taphole were ZnO and Zn₂SiO₄, whereas the substances in the cracks of the carbon brick below the taphole were ZnS. The reaction of Zn with CO, SiO₂, and FeS generates ZnO, Zn₂SiO₄, and ZnS, resulting in volume expansion, which is an important reason for the cracking of carbon brick. Simultaneously, several obvious Zn vapor flow channels were found in the ramming material, through which Zn vapor could enter the carbon brick, causing damage to the carbon brick. Increasing the compactness of the ramming material is beneficial to preventing Zn vapor from entering the carbon brick through the voids in the ramming material, reducing the destructive effect of Zn on the carbon brick and further extending the service life of the blast furnace.</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"91 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928469","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation and properties of ZrO2-strengthened porous mullite insulation materials using Y2O3 additive","authors":"Wang-zhi Yu, Yi-hong Shi, Ping Liu, Yong-wan Wu, Cheng-hao Song, Xian-gong Deng, Xiang Ding, Song-lin Ran, Yi Zhang, Hai-jun Zhang, Hai-liang Deng","doi":"10.1007/s42243-024-01229-y","DOIUrl":"https://doi.org/10.1007/s42243-024-01229-y","url":null,"abstract":"<p>ZrO₂-strengthened porous mullite insulation materials were prepared by foaming technology utilizing ZrSiO₄ and Al₂O₃ as primary materials and Y₂O₃ as an additive. The effects of Y₂O₃ contents on the phase composition, microstructure, mechanical properties, and heat conductivity of the porous mullite insulation materials were investigated. A suitable Y₂O₃ content could promote phase transition of monoclinic ZrO₂ (m-ZrO₂) to tetragonal ZrO₂ (t-ZrO₂), reduce pore size, and improve the strengths of as-prepared specimens. The cold crushing strength and bending strength of as-prepared specimens with a 119 µm spherical pore size using 6 wt.% Y₂O₃ were 35.2 and 13.0 MPa, respectively, with a heat conductivity being only 0.248 W/(m K).</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"15 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mold breakout prediction based on computer vision and machine learning","authors":"Yan-yu Wang, Qi-can Wang, Yong-chang Zhang, Yong-hui Cheng, Man Yao, Xu-dong Wang","doi":"10.1007/s42243-024-01198-2","DOIUrl":"https://doi.org/10.1007/s42243-024-01198-2","url":null,"abstract":"<p>Breakout is the most serious production accident in continuous casting and must be detected and predicted by stable and reliable methods. The sticking region, which forms on the local copper plate and expanded into a “V” shape, is the typical precursor of breakout. Therefore, computer vision technology was exploited to visualize the temperature change rate of the copper plate based on the temperature signals from thermocouples; then, the static and dynamic features of the abnormal sticking region were extracted. Meanwhile, logistic regression and Adaboost models were used to study and identify these features, resulting in the development of a mold breakout prediction model based on computer vision and machine learning. The test results demonstrate that the proposed model can effectively distinguish anomalous temperature patterns and considerably reduce false alarms without any missing reports. As a result, the proposed method could offer valuable insights into the realm of abnormality detection and prediction during continuous casting process.</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"93 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microstructure evolution and its influence on thermoplasticity of wide and thick continuous casting slab with heavy reduction","authors":"Tian-ci Chen, Xin Hu, Tan Zhao, Cheng Ji, Miao-yong Zhu","doi":"10.1007/s42243-024-01188-4","DOIUrl":"https://doi.org/10.1007/s42243-024-01188-4","url":null,"abstract":"<p>After the heavy reduction (HR) process was carried out at the solidification end of the continuous casting slab, the austenite grains were refined by recrystallization, which improved the thermoplasticity of the slab. However, the reduction in deformation during the HR process initiated stress concentration at the slab surface, and the crack risk increased. To effectively evaluate the risk of slab surface cracks under these complex conditions, the effect of the HR on the austenite recrystallization and thermoplasticity of a microalloyed slab surface was investigated by 15-pass reduction thermal simulation according to the wide and thick slab continuous casting process. The softening fraction was introduced as a global internal variable to quantitatively analyze various recrystallized re-refined grains. After the critical strain reaches the critical strain of dynamic recrystallization, a variety of recrystallization modes alternately occur. Among them, the contribution rate of dynamic crystallization to the later refinement reaches more than 50%. The contribution rates of static recrystallization and metadynamic recrystallization to grain refinement are almost the same. The thermoplasticity of the slab surface first increases and then decreases with increasing reduction pass. It was verified by transmission electron microscopy that the main reason for the decrease in thermoplasticity is that the dislocation multiplication rate increases, resulting in a sharp increase in stress and a decrease in thermoplasticity.</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"9 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinct element method simulation of mechanical properties of material layer of pellet belt roasting machine","authors":"Yin-hua Tang, Xing-wang Li, Xu Gao, Tao Yang, Hong-ming Long, Jie Lei","doi":"10.1007/s42243-024-01214-5","DOIUrl":"https://doi.org/10.1007/s42243-024-01214-5","url":null,"abstract":"<p>The thick layer and graded feeding technology of a belt roasting machine is an effective method for improving the production efficiency and quality index of pellet production, and a reasonable design of the mechanical structure of the layer is the basis for optimizing the heat and mass transfer performance of the layer. Janssen effect and von Mises yield criterion were used to establish a simplified mathematical model describing the elastic and plastic deformation of the green pellet under the action of an external force. The mechanical characteristics of extrusion, contact, and elastic–plastic deformation between green pellet particles in the material layer of the belt roasting machine were modeled using EDEM software. For a green pellet size of 12 mm, as the layer height increases from 300 to 1000 mm, the maximum vertical pressure on the pellets increases from 11.64 to 24.01 N, and the porosity decreases from 27.04% to 22.01%. As the layer height increases, the contact between the green pellets becomes more intense, and the force chain structure of the layer becomes more stable; the Janssen effect is observed when the layer reaches 700 mm. The compressive strength of the green pellets is linearly related to the particle size, and the compressive strength increases with an increase in particle size. At a layer height of 600 mm, as the particle size of the green pellets increases from 8 to 20 mm, the maximum vertical pressure increases from 7.54 to 44.16 N, and the porosity increases from 23.20% to 31.47%, while the yield per unit of the layer decreased by 12.1%. Small particles have a more stable force chain structure, larger comparative area, and higher production efficiency; however, their compressive strength is lower. Large particles have higher compressive strength and good permeability in the layer, but the production efficiency is relatively low. In actual production, a variety of factors should be integrated to optimize the feeding, and a multi-granularity graded feeding is the most ideal feeding.</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"41 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140928323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Mg-treatment on transformation of oxide inclusions in X80 pipeline steel","authors":"Ping Shen, Hao Zhang, Kang Xu, Shuai Liu, Jin-xing Jiang, Jian-xun Fu","doi":"10.1007/s42243-024-01208-3","DOIUrl":"https://doi.org/10.1007/s42243-024-01208-3","url":null,"abstract":"<p>In order to investigate the modification behavior and regularity of inclusions in X80 pipeline steel by Mg-treatment, the comparative industrial experiments of Mg-treatment and Ca-treatment in X80 pipeline steel were carried out. Mg and Ca were added to the steel in the form of cored wire after RH (Ruhrstahl-Hereaeus vacuum degassing) process. After adding Ca-containing cored wire, the inclusions were transformed into CaO–Al₂O₃ in the steel. With the progress of smelting, the cleanliness of molten steel became worse, and the equivalent diameter of inclusions was at a higher level. Mg-treatment had a good effect on the modification of inclusions. After Mg-containing cored wire was added to the steel, Al₂O₃ and CaO–Al₂O₃ in the steel were transformed into MgO, MgO·Al₂O₃, and CaO–MgO–Al₂O₃ inclusions, which were basically spherical. The initial precipitated MgO became the core of other inclusions in the steel, which promotes the precipitation of MgO·Al₂O₃. After Mg-treatment, almost no unmodified calcium aluminate inclusions existed in the hot rolled plate, and the cleanliness of the steel was improved. The effect of Ca and Mg on the transformation of inclusions in pipeline steel was studied by thermodynamic calculation, the result of which is consistent with the experimental results.</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"53 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140580447","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of liquid circulation flow rate in RH degasser: improvement of decarburization at low atmospheric pressure","authors":"Gu-jun Chen, Sheng-ping He","doi":"10.1007/s42243-023-01166-2","DOIUrl":"https://doi.org/10.1007/s42243-023-01166-2","url":null,"abstract":"<p>The two-fluid model coupled with population balance model was used for simulating the gas–liquid flow in the Ruhrstahl–Heraeus (RH) degasser. The predicted circulation flow rate was compared with that measured from a water model experiment to validate the mathematical model. Then, influence of snorkel immersion depth on liquid circulation flow rate was numerically investigated under an atmospheric pressure of 101 and 84 kPa, respectively. Predicted result indicates that the circulation flow rate of the RH degasser in the high-altitude area was severely reduced because of the decrease in atmospheric pressure. However, increasing the snorkel immersion depth from 0.5 to 0.7 m can compensate for the decrease in atmospheric pressure. Industrial test result indicates that decarburization rate is significantly enhanced by increasing the snorkel immersion depth. Through optimization, the percentage of heats with a final carbon content less than 0.002 wt.% is significantly increased from 22.0% to 96.4%.</p>","PeriodicalId":16151,"journal":{"name":"Journal of Iron and Steel Research International","volume":"51 1","pages":""},"PeriodicalIF":2.5,"publicationDate":"2024-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140580564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"材料科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}