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Simultaneously achieving high strength and toughness is a dilemma for most high-performance materials, especially solidified epoxy resins (ERs). Here, we used a sustainably sourced tannic acid (TA) molecule, a natural polyphenol hyperbranched polyester, as both a reinforcing and toughening agent for preparing high-strength epoxy adhesives with increased toughness. Benefiting from a highly branched structure and abundant active phenolic hydroxyl groups, TA molecules can be functionalized as multiple physiochemical cross-linking points for generating high-performance ERs. The optimal TA-modified ER (TA/ER-3) shows a high tensile strength of 112.2 ± 3.6 MPa and a high elongation at break of 3.7 ± 0.20%, illustrating increased tensile strength by 37.2% and elongation at break by 32.4% compared with pristine ERs, respectively. Combining scanning electron microscopy and dynamic mechanical analysis reveals that the TA molecules not only promote the curing and cross-linking reaction of epoxy resin but also possess good interface interaction with the matrix, which tune the cross-linking density and dissipate fracture energy through deformation, resulting in strengthening and toughening ERs. This work offers sustainably sourced additives for developing high-performance epoxy adhesives, which can be extended to reinforce other types of polymers or nanomaterials.

Low temperature heating process of the slab has become the mainstream process for producing high quality oriented silicon steel due to its environmental protection, low cost, and high yield. For this process, the number of inhibitors is less and the size is large, resulting in insufficient inhibition, coarsen grains during primary recrystallization, and insufficient driving force for secondary recrystallization, which reduces the magnetic properties of the product. These shortcomings can be improved by optimizing the inhibitors and normalizing processes. The effects of normalizing processes on the microstructure, texture, and precipitations of low-temperature oriented silicon steel containing Sn were studied by OM, SEM, TEM, and EBSD with Fe–3%Si hot-rolled plate as initial material. The experimental results show that the sample has the best performance in terms of microstructure, texture, and precipitations with the two-stage boiling water cooling normalizing process that the heating temperature is 1150 °C, and the normalizing intermediate temperature is 850 °C. With the above parameters, the microstructure is inhomogeneous along thickness. There are more {111}<112> textures, which are favorable to the growth of Goss texture. The proportion of high energy grain boundary reached 54.2%. The precipitates are significantly refined, which enhances the ability to inhibit primary recrystallization. The sub-surface thickness of the hot rolled plate increases from 40.6% to 62.1% with increasing Sn content from 0.01% to 0.11%. The degree of tin segregation at grain boundary increases with the increase of normalizing temperature and the decrease of medium soaking temperature.

Interstitial free (IF) steels are characterized by their interstitial free ferritic matrix due to addition of micro-alloying elements that draw carbon and nitrogen out of matrix to form carbonitrides. The IF steels typically have excellent deep drawing ability, certain mechanical strength, and high plastic deformation performance. In this paper, the microstructure evolution and carbides precipitation behavior during the hot rolling, cold rolling and annealing processes have been studied using both experimental and thermodynamic and kinetic modeling approaches. The strengthening mechanism of Nb–Ti microalloyed IF steel has been investigated. The results of the thermodynamic simulation indicates that the addition of Nb into Ti bearing IF steel promotes recrystallization at 900 °C, leading to fine recrystallized grains. Due to the recrystallization of austenite during the final rolling process, Nb–Ti microalloyed hot rolled plates exhibit finer grain size, fewer substructures, and lower dislocation density compared to the hot rolled plates containing only Ti. Building upon the initial fine and uniform structure, Nb–Ti microalloyed steel maintains a refined structure after undergoing cold rolling and annealing. The study of the carbides precipitation behavior suggests that TiN precipitates at high temperature above 1100 °C, while a substantial amount of (Nb,Ti)C and TiC precipitate at about 900 °C in Nb–Ti and Ti bearing steels, respectively. There is no significantly difference between the amount of carbides in steels hot deformed at 900 °C and in the hot rolled plates, indicating that the carbides mainly precipitate during the hot rolling process. There are negligible carbides precipitated during the coiling process at 600 °C. In Nb–Ti containing steel, Nb and Ti in solid solution are significantly reduced due to the large amount precipitation of (Nb,Ti)C during the final rolling process. The reduction of solid solution Nb effectively promotes the recrystallization of austenite. Therefore, the grains of hot-rolled, cold-rolled, and annealed strips are refined. In addition, there are more small size carbides in Nb–Ti bearing steel than that in Ti bearing steel. Therefore, the higher strength of Nb–Ti steel is mainly from the strengthening effect of grain refinement and carbides precipitation.

As a new-type magnetic state, the cluster glass state in manganite is arousing considerable attention due to its important theoretical value and extensive application prospects in condensed matter physics and spintronics. Due to the complex magnetic interactions, the cluster glass state is difficult to form and regulate in single films. Studies report a new phenomenon that epitaxial strain can regulate the formation of the cluster glass state in LaMnO3(LMO) films. Comparing LMO thin films with different thicknesses grown on a (001)-oriented LaAlO3(LAO) single crystal substrate, we found that the 20-nm-thick LMO film is more likely to form the cluster glass state than the 60-nm-thick and 120-nm-thick films. This can be attributed to the uneven distribution of strain and Mn ions in the depth profile. Our work demonstrates that thickness is an important method for regulating the formation of the cluster glass state in LMO films.

ABSTRACTIn the tapping process of electric arc furnace, aluminium is usually charged into the ladle to remove the oxygen, which increased the cost and reduced steel cleanliness. Recently, a new technology called Tapping Online Refining (TOR) has been developed to solve the problem of peroxidation and excessive inclusions. In this study, both numerical simulation and water experiment were developed to investigate the behaviour of carbon powder supplied with nitrogen into the tapping flowing, the mixing time and powder utilization efficiency under various injection angles. The results showed that when the lance angle was 50°, the macro movement of carbon powder particles could create the best kinetic conditions. Industrial experiment was carried out in a 65t consteel EAF, and showed that, compared with traditional process, the TOR process can increase the alloy utilization by 3–5% and reduce over 40% of the initial precipitation deoxidation inclusions.

In the tapping process of electric arc furnace, aluminium is usually charged into the ladle to remove the oxygen, which increased the cost and reduced steel cleanliness. Recently, a new technology called Tapping Online Refining (TOR) has been developed to solve the problem of peroxidation and excessive inclusions. In this study, both numerical simulation and water experiment were developed to investigate the behaviour of carbon powder supplied with nitrogen into the tapping flowing, the mixing time and powder utilization efficiency under various injection angles. The results showed that when the lance angle was 50°, the macro movement of carbon powder particles could create the best kinetic conditions. Industrial experiment was carried out in a 65t consteel EAF, and showed that, compared with traditional process, the TOR process can increase the alloy utilization by 3–5% and reduce over 40% of the initial precipitation deoxidation inclusions.

ABSTRACTDirectional solidification experiments were carried out on peritectic steels to investigate the microstructure and volume shrinkage. A δ-dendritic structure developed intermittently and was enclosed by γ-austenite at growth rates of 15, 50, and 80 μm s−1. The primary dendritic spacing narrowed and the average spacing of dendrites decreased as the growth velocity increased. The functional relationship between the secondary dendrite arm spacing and cooling rates was established by statistical analysis. The influence of cooling rate on crack formation was analysed as a function of volume shrinkage. Reducing the cooling rate of the solidification delayed a massive type of peritectic transformation away from the ZST–ZDT brittle zone, thus reducing the probability of crack formation.

Directional solidification experiments were carried out on peritectic steels to investigate the microstructure and volume shrinkage. A d-dendritic structure developed intermittently and was enclosed by ?-austenite at growth rates of 15, 50, and 80?µm s-1. The primary dendritic spacing narrowed and the average spacing of dendrites decreased as the growth velocity increased. The functional relationship between the secondary dendrite arm spacing and cooling rates was established by statistical analysis. The influence of cooling rate on crack formation was analysed as a function of volume shrinkage. Reducing the cooling rate of the solidification delayed a massive type of peritectic transformation away from the ZST–ZDT brittle zone, thus reducing the probability of crack formation.

The development of an environmentally friendly binder can immensely benefit and promote the BF slag fiber industry. Accordingly, in this study, fiber insulation pipes were prepared using water glass, polyvinyl alcohol (PVA), and PVA–glutaraldehyde (GA); moreover, their bulk density, moisture absorption capacity, and thermal conductivity coefficient were measured and compared. The results demonstrated that the values of these three parameters depend on the binder concentration and dosage under certain fiber quality, pipe sizes, and manufacturing process conditions. The best binder composition was proven to be that of PVA–GA, prepared using 3 wt% PVA and 5 wt% GA herein, which facilitated reduction in the bulk density and improvement of the waterproof properties and insulation performance of the slag fiber pipes.

Since the discovery of MXene in 2011, its physical and chemical diversity has led to MXene being considered as a potential 2D material with a wide range of applications due to its tunable structure and rich surface chemistry. This review focuses on summarizing the preparation methods of MXene, MXene-based and MXene-derived two-dimensional photocatalysts and their application research progress in the field of photocatalysis. The preparation methods of MXene are described in detail from three aspects: wet etching method, anhydrous etching method and direct synthesis method. Meanwhile, the strategies for the insertion and layering of multilayer MXene and the synthesis process of MXene-based and MXene-derived photocatalysts are described. In addition, we present recent research on MXene-based and MXene-derived photocatalysts for environmental and energy applications, including water decomposition to release H2, CO2reduction, nitrogen fixation, and other photocatalytic applications. Finally, challenges and perspectives for MXene research are presented.