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Segregation of interface elements is the main factor affecting the corrosion activity of microareas around Al2O3 inclusions rather than galvanic corrosion. In this work, the effects of segregation of Cu, V, Ni, Mo, B, and P elements on the interfacial bonding strength and microareas corrosion activity around Al2O3 inclusions are analyzed in detail using 3D atomic probe and first‐principles calculations. In the results, it is shown that Cu, V, Mo, B, and P elements reduce the stability of the α‐Fe/Al2O3 interface. In addition, the segregation of Cu, V, Mo, B, and P elements at the interface also enhances the adsorption capacity of Cl and ultimately improves the microarea corrosion activity around Al2O3 inclusions. Ni element can enhance the stability of α‐Fe/Al2O3 interface, and the segregation of Ni element at the interface weakens the adsorption capacity of Cl and ultimately reduces the microarea corrosion activity around Al2O3 inclusions. [ABSTRACT FROM AUTHOR]

Microglial polarization and associated inflammatory activity are the key mediators of depression pathogenesis. The natural Smilax glabra rhizomilax derivative engeletin has been reported to exhibit robust anti‐inflammatory activity, but no studies to date have examined the mechanisms through which it can treat depressive symptoms. We showed that treatment for 21 days with engeletin significantly alleviated depressive‐like behaviours in chronic stress social defeat stress (CSDS) model mice. T1‐weighted imaging (T1WI), T2‐weighted imaging (T2WI) imaging revealed no significant differences between groups, but the bilateral prefrontal cortex of CSDS mice exhibited significant increases in apparent diffusion coefficient and T2 values relative to normal control mice, with a corresponding reduction in fractional anisotropy, while engeletin reversed all of these changes. CSDS resulted in higher levels of IL‐1β, IL‐6, and TNF‐a production, enhanced microglial activation, and greater M1 polarization with a concomitant decrease in M2 polarization in the mPFC, whereas engeletin treatment effectively abrogated these CSDS‐related pathological changes. Engeletin was further found to suppress the LCN2/C‐X‐C motif chemokine ligand 10 (CXCL10) signalling axis such that adeno‐associated virus‐induced LCN2 overexpression ablated the antidepressant effects of engeletin and reversed its beneficial effects on the M1/M2 polarization of microglia. In conclusion, engeletin can alleviate CSDS‐induced depressive‐like behaviours by regulating the LCN2/CXCL10 pathway and thereby altering the polarization of microglia. These data suggest that the antidepressant effects of engeletin are correlated with the polarization of microglia, highlighting a potential avenue for future design of antidepressant strategies that specifically target the microglia. [ABSTRACT FROM AUTHOR]

The effect of spinel powder on the fracture behavior and mechanical properties of lightweight magnesia‐based refractories containing microporous magnesia aggregates with high apparent porosity (37.4%) were investigated by the wedge splitting test (WST) with the digital image correlation and acoustic emission. With the addition of spinel powder, lightweight magnesia spinel refractories showed a higher cold compressive strength compared with lightweight pure magnesia refractories. From the WST, the addition of spinel powder increased the specific fracture energy and characteristic length of lightweight magnesia spinel refractories, which improved the crack propagation resistance. The increased tortuosity of main crack and a higher ratio of crack propagation along the aggregates/matrix interface were main reasons for reducing the brittleness of lightweight magnesia spinel refractories. Besides, acoustic emission (AE) signal activity indicated that the propagation of pregenerated micro‐cracks by the thermal mismatch and the development of fracture progress zone were primary ways to consume energy in lightweight magnesia spinel refractories. The reduced proportion of crack propagation within aggregates was also detected by the peak frequency of AE signals in lightweight magnesia spinel refractories. For microporous magnesia aggregates with high apparent porosity (37.4%), lightweight magnesia spinel refractories also showed reduced brittleness fracture behavior than lightweight pure magnesia refractories. [ABSTRACT FROM AUTHOR]

Cu is an austenite‐forming element in duplex stainless steel, and the precipitation of Cu‐rich phase can improve the strength of the alloy. However, the role of Cu element in the corrosion resistance of stainless steel is widely controversial. Herein, the effects of different Cu content on the formation of inclusions and the pitting resistance of duplex stainless steel are studied by using potentiodynamic anodic polarization test, immersion corrosion, scanning electron microscope, and electron probe microanalysis. The results show that the pitting potential decreases significantly with the increase of Cu content, which greatly reduces its ability to resist Cl− corrosion. The reason is that Cu increases the driving force for the formation of Al‐containing oxides, which increases the number and size of Al‐containing inclusions formed in the process of melting and solidification. At the same time, Cu promotes the formation of Cr‐depleted zone, which promotes the formation of microcracks and pitting corrosion between steel matrix and inclusions in duplex stainless steel. [ABSTRACT FROM AUTHOR]

Titanium‐bearing (Ti‐bearing) microalloyed steels have high strength and toughness by grain refinement effect of carbonitride precipitates. However, they can induce surface cracks of continuous casting slab when the Ti alloyed content is high. A microalloyed steel with Ti content (0.10–0.15 wt%) is carried out by thermalmechanical simulator over 600–1350 °C to analyze hot ductility evolution mechanism. Fracture surface morphology, phase transition, and behavior of precipitates of the tensile samples are investigated by experimental detection and thermodynamic calculation. The ductility–temperature curves show that the third brittle temperature range is 600–890 °C, which is mainly attributed to the thin proeutectoid ferrite film and precipitated titanium carbonitride particles, widening the embrittlement temperature ranges through of steel. In addition, the tensile samples at 890–1350 °C have good hot ductility, indicating the dynamic recrystallization of deformed austenite can trigger grain boundaries migration away from cracks and avoid the side effect of the Ti (C,N) particles on hot ductility. The first brittle temperature range of 1350 °C‐melting point is mainly ascribed to the partial melting of the grain boundaries with element segregation of sulfur and phosphorus, and microporosity loose among dendrites. [ABSTRACT FROM AUTHOR]

Effects of sintering atmosphere on the microstructure and strength of magnesite were investigated using magnesite powder as raw material through X‐ray diffraction, scanning electron microscopy, mercury porosimetry measurement, and so on. The results showed that the sintering atmosphere strongly affected the sintering behavior of magnesite. The specimens sintered in the reducing atmosphere had more and finer micro‐sized pores inside the MgO particles compared with that in the oxidizing atmosphere at the same sintering temperature. Besides, MgO refractory raw material containing porous MgO microparticles with core–shell structure was obtained through the carbothermal reduction of MgO microparticles and subsequent oxidation of Mg vapor at the surface of MgO particles at 1500°C in the reducing atmosphere. At the reducing atmosphere and 1500°C, the microporous MgO refractory raw material with the core–shell structure of external dense and internal porous had an apparent porosity of 22.1% and a compressive strength of 51.6 MPa. [ABSTRACT FROM AUTHOR]

To realize an industrial production of a cerium‐treated electroslag remelted H13 steel, electroslag remelting (ESR) of H13 steel using a CaF2–CeO2–CaO–Al2O3 system slag combined with a Si–Ca reductant addition is studied. The influence of the Al2O3 content in the slag on the cerium treatment effect of cerium‐oxide‐containing slag is investigated to determine the appropriate slag. A 52.2 wt% CaF2–26.7 wt% CeO2–17.8 wt% CaO–3.3 wt% Al2O3 slag (RE‐Slag) is employed for the industrial ESR production of H13 steel. An H13 steel remelted by a 70 wt% CaF2–30 wt% Al2O3 slag (CA‐Slag) is used for comparison. Al2O3 can suppress the reduction of cerium oxide by changing the activities of slag components. ESR with RE‐Slag achieves a cerium treatment of H13 steel. However, an uneven distribution of Ce is obtained due to the limitation of the reductant addition method. The H13 steel remelted with RE‐Slag (RE‐Slag‐H13) has higher cleanliness, finer dendritic structures, and finer primary carbides than those of the steel remelted with CA‐Slag (CA‐Slag‐H13). Compared to the forged CA‐Slag‐H13 steel, the banded segregation of the RE‐Slag‐H13 steel is suppressed, and the impact toughness is increased by 30%. [ABSTRACT FROM AUTHOR]

The apparent contact angles between the molten steel with different [Al] contents (w[Al]) from 0.002% to 0.831% (mass fraction) and the microporous MgO (MM) substrates are measured at 1823 K using the sessile drop method. In particular, the contact angles of No. 1 (w[Al] = 0.002%) and No. 5 (w[Al] = 0.831%) molten steels gradually increase with time at the initial stage. As w[Al] increases from 0.002% to 0.831%, the transformation route of interfacial products between molten steel and the MM substrate is MgO–FeO → MgO·Al2O3 → CaO·2Al2O3 + MgO·Al2O3. The w[Al] of No. 1 molten steel is small, and the dissolution of CaO·ZrO2(s) in the substrate is mainly affected by FeO. As w[Al] increases gradually, [Al] consumes the (MgO) contained in CaO·MgO·SiO2 (CMS), and turns the CMS into (CaO·SiO2) slag layer, which promotes the CaO·ZrO2(s) dissolving and thus increasing the interaction area percentage. When w[Al] is 0.831%, [Al] can react with (CaO·SiO2) slag layer or CaO·ZrO2(s) to form CaO·2Al2O3(s). [ABSTRACT FROM AUTHOR]

High‐entropy transition‐metal (IVB–VIB) carbide (HETMC) ceramics consisting of multiple principal components generally correspond to higher configuration entropy, and exhibit better overall performance. However, they also present certain synthesis challenges, for example, in the synthesis of a three‐dimensional six‐principal‐component HETMC aerogel. In the present work, as an example a novel (Ti0.167Cr0.167V0.167Mo0.167Nb0.167Ta0.167)C aerogel was prepared at a relatively low temperature of 1773 K by an in‐situ carbothermal reduction/partial sintering technique following the successful preparation of (Ti0.2V0.2Mo0.2Nb0.2Ta0.2)C and (Ti0.2Cr0.2Mo0.2Nb0.2Ta0.2)C five‐principal‐component HETMC aerogels. The synthesized 6‐HETMC aerogel exhibited a homogeneous microstructure with grain phases and pores of 100–300 nm and 0.2–10 μm, respectively, a density of 0.45 g cm−3, a high porosity and compressive strength of 94.5% and 0.8 MPa, respectively, a low thermal conductivity of 0.128 W (m K)−1 at 298 K, and a good high‐temperature stability at least up to 1673 K in Ar. This research provided a novel strategy for future development of HETMC ceramic aerogels for high‐temperature applications. [ABSTRACT FROM AUTHOR]

Seven microporous MgO–Al2O3 ceramics with an Al2O3 content of 15–90 wt% were prepared using Al(OH)3 and calcined magnesite as raw materials. A wet mixing process was employed during sample preparation to transform the calcined magnesite with a larger particle size to smaller Mg(OH)2 particles. The in situ decomposition synthesis method and the Kirkendall effect were utilized to produce and control the pore structure of the microporous MgO–Al2O3 ceramics. There were two kinds of pores in the microporous MgO–Al2O3 ceramics. The first one resulted from the in situ decomposition of Al(OH)3 and Mg(OH)2 particles, which were small and equally distributed. Another one originated from the position of the Mg(OH)2 particles due to the Kirkendall effect caused by MgO diffusion. They were similar in size to the Mg(OH)2 pseudomorph particles. Simultaneously, the Al2O3 content affected the packing behavior and the spinel formation, which changed the characteristics of the pores and necks among the particles. These mechanisms also affected the strengths of the microporous MgO–Al2O3 ceramics. Thus, when the Al2O3 content was 45–90 wt%, the microporous MgO–Al2O3 ceramics had a high compressive strength (10.0–18.3 MPa) and apparent porosity (52.2%–58.4%). [ABSTRACT FROM AUTHOR]

A fluid–solid‐coupled numerical model is established on the motion and removal of inclusions in the continuous casting tundish with a multichannel filter. The flow field, heat transfer, and motion of inclusions in continuous casting tundish are simulated. The erosion of the lower part of the weir and filter is the most serious; at the casting speed of 2.2 m min−1, the maximum displacements in the upstream and downstream directions are 4.25 and −3.81 mm, respectively. The casting speed effect on the flow pattern and removal of inclusions is investigated. The weir and filter erosion increases with increased casting speed, the total removal efficiency is raised, and the dead zone fraction is reduced. After the casting speed exceeds 2.2 m min−1, the total removal efficiency of inclusions starts to decline. When the casting speed is raised from 1.4 to 3.0 m min−1, the share of inclusions removed by the filter drops from 8.2 to 2.5%, which is nearly 70%. [ABSTRACT FROM AUTHOR]

It is aimed to explain different tensile elongations in 18Cr–8Ni austenitic stainless steel (ASS) with various microstructures having the same yield strength by comparing the deformation mechanisms. The as‐received ASS is cold‐rolled (CR) at room temperature with thickness reductions of 10% and 90% (achieved following 14 passes). The ultra‐fine grain/fine grain (UFG/FG, average grain size (diameter): 0.5–2 μm) structure is developed by annealing the 90% CR structure at 850 °C over 300 s. The optical, scanning and transmission electron microscope, electron backscatter diffraction, and X‐ray diffraction techniques are applied to the microstructural features. The as‐received specimen contained equiaxed austenite and equiaxed dislocation cells, stacking faults, deformation twins (DTs), and strain‐induced martensite (SIM) coexist in the 10% CR and UFG/FG samples. Tensile tests are conducted, and the results reveal that 10% CR and UFG/FG structures exhibited similar yield strengths (550 MPa) under conditions of varying elongation properties, which is attributed to differences in the microstructure‐dependent deformation mechanisms. Dislocation slip (≈10 area%; newly formed), DTs, and SIM (≈44 vol%; newly formed) are observed in the 10% CR structure. The presence of numerous dislocation slips (≈50 area%; newly formed) and a small amount of DTs and SIMs are observed in UFG/FG structure. [ABSTRACT FROM AUTHOR]

Rare earth elements have unique outer electronic structure, variable valence, and strong chemical activity; however, their occurrence state in the rust layer and influence on the invasion state of corrosion atoms are still unclear. Herein, using a combination of experiment and first‐principles calculation, the occurrence state of La in the rust layer of low‐alloy high strength steel, the phase composition, compactness and stability of the rust layer, and the invasion state of corrosion atoms before and after La alloying are studied. The results show that La exists in the corrosion products in the form of a solute atom. La increases the concentration of corrosion‐resistant elements Cr and Mo in the rust layer but does not change the phase composition. La is conducive to stabilizing Cl atoms in α‐FeOOH and β‐FeOOH, so as to protect the steel matrix from Cl. La atoms inhibit the dissolution of Cl atoms into γ‐FeOOH and Fe3O4 structures and hinder their formation. [ABSTRACT FROM AUTHOR]

Gas‐mediated sonodynamic therapy (SDT) has the potential to become an effective strategy to improve the therapeutic outcome and survival rate of cancer patients. Herein, titanium sulfide nanosheets (TiSX NSs) are prepared as cascade bioreactors for sequential gas–sonodynamic cancer therapy. TiSX NSs themselves as hydrogen sulfide (H2S) donors can burst release H2S gas. Following H2S generation, TiSX NSs are gradually degraded to become S‐defective and partly oxidized into TiOX on their surface, which endows TiSX NSs with high sonodynamic properties under ultrasound (US) irradiation. In vitro and in vivo experiments show the excellent therapeutic effects of TiSX NSs. In detail, large amounts of H2S gas and reactive oxygen species (ROS) can simultaneously inhibit mitochondrial respiration and ATP synthesis, leading to cancer cell apoptosis. Of note, H2S gas also plays important roles in modulating and activating the immune system to effectively inhibit pulmonary metastasis. Finally, the metabolizable TiSX NSs are excreted out of the body without inducing any significant long‐term toxicity. Collectively, this work establishes a cascade bioreactor of TiSX NSs with satisfactory H2S release ability and excellent ROS generation properties under US irradiation for programmed gas–sonodynamic cancer therapy. [ABSTRACT FROM AUTHOR]

Hypoxia‐inducible factor 2α (HIF2α) plays a pivotal role in breast tumor growth and metastasis. However, the regulatory mechanisms of HIF2α protein stability remain poorly understood. The precise role of the deubiquitinase (DUB) ubiquitin‐specific peptidase 5 (USP5) in breast cancer and the underlying mechanism remains largely unknown. Here, we identified USP5 as a novel DUB for HIF2α. Physically, USP5 interacts with HIF2α and protects HIF2α from ubiquitin‐proteasome degradation, thereby promoting the transcription of HIF2α target genes, such as SLC2A1, PLOD2, P4HA1, and VEGFA. USP5 ablation impairs breast cancer cells proliferation, colony formation, migration, and invasion. Moreover, USP5 is highly expressed in breast cancer, and the protein levels of USP5 are positively correlated with HIF2α protein levels in human breast cancer tissues. Importantly, high levels of USP5 leads to poor clinical outcome in patients with breast cancer. Collectively, USP5 stabilizes HIF2α through its DUB activity and provides a potential therapeutic target for breast cancer. [ABSTRACT FROM AUTHOR]

Refining ladle is generally the last inclusion‐removal vessel before the continuous casting of steel, so, it has a vital effect on the final steel quality. In this work, degradation process of a cement‐free Al2O3‐MgAl2O4 refractory in contact with molten steel/slag in the metal bath area of a Ruhrstahl Heraeus (RH) refining ladle was investigated. A reaction product layer with the formation of ferrospinel (hercynite) and Fe‐rich phases was observed, suggesting that the interactions/reactions between the refractory lining and the molten steel should also be considered to have a better understanding of overall degradation mechanism of the refractory served under the RH refining conditions. The two types of alumina grains in the refractory, sintered and fused alumina, were attacked in an active way and a passive way, respectively. The effect of the crack generation and steel infiltration on degradation of the refractory was also discussed in detail, based on the microstructural characterizations. [ABSTRACT FROM AUTHOR]

Demand for energy saving in steelmaking process, lightweight refractories have attracted great attentions for the excellent thermal insulation. Herein, the corrosion behavior of the lightweight magnesia in the high basicity tundish slag is explored, and compared with that of fused magnesia. The results show that the impurities in the fused magnesia cause more dissolution of magnesia into slag after 60 min. Different from fused magnesia, the penetration layer is found in the lightweight magnesia, where the intercrystalline CaZrO3–ZrO2 phases are dissolved by the slag. The micropores in the lightweight magnesia provide passages for slag infiltration, but also accelerate the supersaturation of slag in refractory and impede the mass transfer. Furthermore, the residual CaZrO3–ZrO2 phases in transition layer hinder the further slag infiltration. After 60 min holding, the MgO content in molten slag contacted with lightweight magnesia is lower, implying that the lightweight magnesia is the promising refractory for tundish lining. [ABSTRACT FROM AUTHOR]

Formation of a dense layer on corroded interface to suppress corrosion is always desired, but it is controlled by numerous environmental conditions. In this work, corroded microstructures of MgO/Al2O3‐SiC‐C refractories in metal bath area of ladle furnace were investigated after industrial trails. A liquid‐phase isolation layer in which MgO islands and liquid phases was established on the corroded interface of refractories with 6 wt% coarse/fine SiC‐additive. The formed isolation layer against steel/slag attacks led to an approximate 30% improvement in corrosion resistance than that of refractory with 3 wt% fine SiC‐additive. More importantly, the liquid‐phase isolation layer blocked the direct mass transfer between molten steel and refractories while it decreased exogenous pollution from refractories. SiC‐additive affected the formation process of isolation layer by controlling the generation/migration of Mg(g) on refractory' surface. A further formation mechanism of liquid‐phase isolation layer was discussed in detail and role of SiC was elucidated. [ABSTRACT FROM AUTHOR]

Six microporous MgO‐Al2O3 refractory aggregates were prepared with Al(OH)3 and two different types of magnesite powders via an in‐situ decomposition pore‐forming technique. One magnesite powder contained more CaO (Magnesite C), the other one contained more SiO2 and Al2O3 impurities (Magnesite SA). Effects of magnesite powder type and content (11 wt.%, 36 wt.% and 77 wt.%) on the phase compositions, microstructures and mechanical strengths of the prepared microporous aggregates were investigated by X‐ray diffractometry (XRD), mercury porosimetry measurements, and scanning electron microscopy (SEM), etc. With the addition of 11 wt.% and 77 wt.% magnesite, the type of magnesite had only a small effect on the microporous corundum‐spinel and periclase‐spinel aggregates, while great influence on the microporous spinel aggregates was observed with 36 wt.% addition. This was mainly because of the sintering process with liquid phase. The best microporous MgO‐Al2O3 refractory aggregates, which had an apparent porosity of 39.1%, a median pore size of 3.38 μm and a compressive strength of 66.3 MPa, were prepared by using 36 wt.% Magnesite C. This work has practical significance for the efficient utilization of magnesite and the development of energy‐saving lightweight MgO‐Al2O3 refractories. [ABSTRACT FROM AUTHOR]

Functional refractory materials for flow control devices of molten steel in continuous casting used to be prepared from Al2O3–C refractories containing dense corundum aggregates. According to the traditional concept, the denser the refractories, the higher the strength of refractories. However, we prepared a new lightweight Al2O3–C refractory material using microporous corundum aggregates instead of dense corundum aggregates, which were reinforced by in situ formed SiC whiskers. A comparative analysis of microstructures and properties was carried out for conventional and lightweight Al2O3–C refractories with and without Si powder addition. We showed that microporous aggregates formed a better aggregate/matrix interface bonding and an improved distribution of SiC whiskers. The SiC whiskers formed not only in the matrix, but also inside of the microporous aggregates and at the aggregate/matrix interface by a vapor‐solid reaction mechanism. Due to the formation of a microporous aggregate/matrix interface reinforced by SiC whiskers, the crack propagation along the aggregate/matrix interface was suppressed, whereas the percentage of cracks propagating within the aggregates was enhanced. Thus, the synergy between in situ formed SiC whiskers and microporous aggregates resulted in a significant higher strength of lightweight Al2O3–C refractories compared to conventional ones. The results therefore provide an original strategy to strengthen Al2O3–C refractories. [ABSTRACT FROM AUTHOR]

The oxidation behavior and subsurface phase transformation of novel high Mn cryogenic steel Fe–(0.35–0.45)C–(0.2–0.25)Si–(25–25.8)Mn–(3–5)Cr are investigated in the temperature range of 600–1200 °C under air atmosphere. The results show that the weight gain curves of oxidation with time are in good agreement with linear equations during 90 min holding below 800 °C, implying that the interface reaction is the rate‐controlling process. Above 900 °C, the oxidation reaction kinetics is governed by the parabolic rate law due to the formation of thick oxide scale. The inner oxide scale mainly consisting of Cr oxide at 1000 °C is thicker than that at 900 °C, but the thickness of the whole oxide scale is thinner than that at 900 °C. After 90 min holding, the oxidation weight gain at 900 °C is more than that at 1000 °C, which is dominated by the combined effect of thermodynamic and kinetic factors. The Mn‐depleted zone occurs in the steel matrix epidermis, leading to the subsurface phase transformation. The γ‐Fe transforms into α‐Fe in the steel matrix epidermis, which will result in deterioration of steel properties. Protective atmosphere should be adopted for heat treatment process of the novel high Mn steel. [ABSTRACT FROM AUTHOR]

Ladle refining is an efficient process for improvement of quality of steel on secondary metallurgy under harsh conditions. Magnesia refractories with high purity are important raw materials for ladle lining in high‐quality steel production. However, the penetration by CaO–MgO–SiO2 slags damages magnesia refractories, which considerably limits their service life. Abundant grain boundaries in magnesia create channels for slag penetration and lead to the destruction of the structure. The effect of the microstructure on the slag corrosion behavior of magnesia aggregates requires further systematic investigation. In this study, a corrosion model was established to describe the slag penetration process of magnesia aggregates. The effects of the grain‐boundary size and slag CaO/SiO2 mass ratio (C/S ratio) on slag penetration were investigated, and the possibility of the microstructure optimization of magnesia aggregates was discussed. The results indicated that magnesia aggregates exhibited excellent slag resistance for slag with a C/S ratio above 1.5 or even 2.0. When the slag C/S ratio was lower than 1.5, the dissolution rate of magnesia decreased more rapidly with the increase in the slag C/S ratio. In addition, the much smaller grain‐boundary size increased the slag penetration resistance by promoting the formation of a dense isolation layer and inhibiting further penetration processes. The calculation results agreed well with the experimental results, suggesting that the corrosion model is promising for predicting slag corrosion. [ABSTRACT FROM AUTHOR]

β‐Sialon(z = 2, Si4Al2O2N6)/ZrN composite powders have been synthesized from coal ash, zircon, and active carbon at 1550°C for 6 hours, and β‐Sialon(z = 2)/ZrN/ZrON‐based composite ceramics (SZZCCS) have been prepared from as‐synthesized β‐Sialon/ZrN composite powders via pressureless sintering process. The effects of sintering temperatures (1450, 1500, 1550°C) on the phase compositions, microstructures, linear shrinkage ratio, bulk density, and oxidation characteristics of the SZZCCS were investigated in detail, and the oxidation process was also analyzed. It was found that the dense SZZCCS could be prepared at 1550°C for 1 hour, and they mainly consisted of β‐Sialon(z = 2), ZrN, and ZrON. The ZrN and ZrON particles were uniformly distributed on the β‐Sialon matrix. The sintering properties of the SZZCCS were greatly improved with increasing the sintering temperature. The SZZCCS sintered at 1550°C for 1 hour possessed excellent oxidation resistance at 900°C for 6 hours due to their dense microstructures. [ABSTRACT FROM AUTHOR]

Desulfurization and characterization of inclusions during ESR of dual alloy ingot were experimentally studied. The composition and inclusions in electrode and ESR ingot were analyzed by means of various analytical techniques. The results show that the size of inclusions in ingot is smaller and more uniform. The single larger (Mn,Cr)S inclusion (11.6 µm) is found in NiCrMoV electrode. But, no single (Mn,Cr)S inclusion is found in NiCrMoV and CrMoV zones in dual alloy ingot, whereas found in transition zone (TZ). The size of inclusions in TZ is larger than that in NiCrMoV and CrMoV zones due to the inclusions with a thicker (Mn,Cr)S layer and large (Mn,Cr)S inclusions in TZ. Thermodynamic calculations show that (Mn,Cr)S inclusions with high x(Mn)/x(Cr) can precipitate at the solidification front of TZ due to the enrichment of [Mn] and [S] in residual liquid steel. To eliminate (Mn,Cr)S inclusions, a deeper desulfurization is needed. The sulfur content decreases from 0.039 (mass pct) to 0.0171% in NiCrMoV zone and from 0.011 to 0.0017% in CrMoV zone. The gasifying desulfurization plays a dominate role, the ratio of gasifying desulfurization is 92.2%. [ABSTRACT FROM AUTHOR]

In this work, n-type Bi2Te2.7Se0.3 bulks are prepared by resistance pressure sintering technique from different particle sized powders, and the microstructure and electrical transport properties are investigated as function of the initial particle size distribution. With the initial particle size decreasing, more antisite defects, grain-boundaries and interface defects are introduced, and lead to a larger carrier concentration due to donor-like effect and a lower mobility due to the increasing grain boundary and carrier scattering, which results in a lower Seebeck coefficient and electrical resistivity. As a result, a maximum power factor of about 2.89 mW mK−2 at room temperature is achieved for the bulk sintered from the mix powders with different particle size distribution due to the optimization of the carrier concentration. The band gaps and the intrinsic excitation temperature are effectively adjusted by controlling the particle size in a narrow distribution. The sample sintered from the powders below 400 mesh has the highest average power factor above 2.44 mW mK−2 in the whole testing temperature range due to the improving band gaps and intrinsic excitation temperature. [ABSTRACT FROM AUTHOR]

The effect of acid-soluble aluminum (Als) content on precipitation behavior of precipitates, microstructures, and textures of annealed hot-rolled grain-oriented silicon steels are investigated. The results show that a large amount of fine AlN and a little amount of MnS-AlN composite can be obtained after hot band annealing. More fine precipitates are formed in specimen containing higher content of Als. Als content plays a negligible effect on the Goss texture formation during hot band annealing and similarly weak Goss texture component can be found in subsurface of annealed hot-rolled bands with different Als content. It is also found that MnS and AlN can have a combined inhibiting impact on the grain growth. AlN plays a more critical role on the inhibition of grain growth during hot band annealing. The more uniform and finer grains in subsurface of annealed hot-rolled band are due to the effective inhibiting effect of finely and uniformly dispersed precipitates in steel with higher Als content. [ABSTRACT FROM AUTHOR]

In the present study, the experiments for the phosphorus equilibrium partition between CaO-SiO2-Fe tO-P2O5 slags with Na2O or K2O addition and solid pure iron foil were performed at 1573, 1623, and 1673 K, respectively. The experimental results showed that both Na2O and K2O addition can enhance the dephosphorization ability of CaO-SiO2-Fe tO-P2O5 based slags and they have similar dephosphorization ability under the same temperature and main slag composition. The phosphorous partition ratio between slag and carbon-saturated hot metal increased with the increase of basicity with a peak value in the range of R around 1.3-1.5. The phosphorous partition ratio decreased with the increasing of ( w(CaO) + w(Na2O))/ w(Fe tO) value in slags. The dephosphorization ability of CaO-SiO2-Fe tO-P2O5 based slags was relatively higher when the ( w(CaO) + w(Na2O))/ w(Fe tO) values fell in the range of 0.5-0.8. The phosphorous partition ratio decreased with the temperature increase. The linear relationships between the logarithm phosphorous partition ratio and the reciprocal of temperature were obtained for CaO-SiO2-Fe tO-P2O5 based slags with Na2O. The information provides by present study would be useful for optimization of dephosphorization in hot metal pretreatment. [ABSTRACT FROM AUTHOR]

The particles and microstructural characteristics in the simulated heat‐affected zone (HAZ) of the Al–Ti deoxidized steel with 0.05% Ce treatment are investigated using in situ, optical, and electron microscopes and an electron backscattered diffraction analysis, and compared with the Al–Ti deoxidized steel with Ca treatment. The results reveal that the fine CeAlO3 inclusions and nanoscale (Ti, Nb)N precipitates are formed in the Ce‐bearing steel instead of the Ca–Al oxides surrounded by TiN and nanoscale (Ti, Nb)N precipitates in the Ca‐bearing steel. The nanoscale precipitates with higher density in the Ce‐bearing steel can effectively pin austenite grain boundary, and the finer austenite grain is obtained during the welding thermal cycle. The inclusions in both steels are detrimental to the acicular ferrite nucleation. Thus, the transformation from austenite to bainite occurs actively, and bainite packets with different lengthening directions divide the prior austenite into several small regions at intermediate temperature. The fine‐grained microstructure is obtained in the simulated HAZ of the Ce‐bearing steel due to the pinning effect of finer precipitates with higher density and the formation of the bainite packets with high‐angle grain boundary. [ABSTRACT FROM AUTHOR]