Combustion behavior of single pulverized coals (PCs) and co-combustion characteristics of anthracite (AT) and bituminite (BT) blends with 20 wt.% volatile were studied by thermogravimetric experiments. The results indicated that reaction characteristics of PCs were closely related to their functional group structure and consequently, the pyrolysis of PCs with highly active functional groups initiated

The formation and properties of precipitates in wrought Ni-based superalloys with different W contents during long-term exposure to high temperatures were investigated. The scanning electron microscope, transmission electron microscope, and chemical phase analysis were used to investigate the formation and properties of precipitates. It is found that with increasing W content, the quantity and thermal

To reduce internal residual stress and homogenize micro-property of hot-rolled ferrite steel, the cold compression deformation method with small reduction rate has been performed in the hot-rolled samples, and X-ray diffraction and nanoindentation test have been used to detect the residual stress and micro-property. The samples with deformation rate of 0–5.59% or annealing at 550 °C are analyzed. The

The effects of traditional heat treatment (quenching and then tempering) and deep cryogenic treatment on the microstructure and mechanical properties of a low-carbon high-alloy martensitic bearing steel were studied by Rockwell hardness test, X-ray diffractometry, scanning electron microscopy and transmission electron microscopy. The results show that the deep cryogenic treatment promotes the transformation

The effects of 0.01–0.11 wt.% Zr on the inclusions, microstructure, tensile properties, and impact toughness of the China low activation martensitic steel were investigated. Results showed that Zr exhibits good deoxidation and desulfurization abilities. The scanning electron microscope was used to examine the inclusions in the ingots. The main inclusions in the alloys were Zr–Ta–O, Zr–O, and Zr–O–S

During multi-jet cooling, the complex hydrodynamic characteristics caused by the interaction between jets will affect the heat transfer of the plate. To further clarify the heat transfer characteristics in different flow regions, the double-jet cooling experiments were completed on a 50-mm-thick plate with the initial cooling temperature and jet angle in the range of 300–900 °C and 0°–60°, respectively

The austenite stability and the mechanical properties in a typical medium Mn grade steel, i.e., 5Mn steel, were investigated under a wide range of strain rates through the combination of experimental and theoretical methodologies. The obtained results indicate that austenite is more stable at a high strain rate, which is due to the suppression of the austenite to martensite transformation. This suppression

The core of the long-life copper stave was to ensure the stability of the slag layer, and the uniform distribution of the slag layer was beneficial to restrict the generation of the overthick slag layer. A novel model for calculating the thickness and distribution of the slag layer in the part of copper stave was established based on the finite element theory through the ANSYS birth-death element technology

With significant emphasis on reducing the turbulence in the bath and the need for effective distribution of metal along the roller length in twin-roll casting, a novel submerged entry nozzle (SEN) configuration with two “gap regions” was provided. The “gap regions” of the new SEN divide the bath into two parts, the “upper melt bath” (casting region) and the “lower melt bath” (rolling region). The newly

Profile requirements of silicon steel strip are extremely high and the thickness difference of cold-rolled products is usually less than 7 μm, and the profile quality of hot-rolled strip is the key to ensure the thickness difference of cold-rolled products. In order to produce the silicon steel strip with high-precision shape, the concept of quasi-rectangular rolling during hot continuous rolling was

The partitioning of nitrogen atoms and its effect on the retained austenite content (RAC) during quenching and partitioning (Q&P) process were investigated by dilatometry, X-ray diffraction, and field emission transmission electron microscopy with energy-dispersive spectrometer mapping in a 00Cr13Mn8N steel. Nitrogen partitioning by diffusion of N atoms from martensite to austenite occurred at 400 °C

Pulverized coal utilization in the blast furnace is decided by the particle flow and combustion behaviors in the raceway. Under a specific operating condition, these behaviors are directly related to the lance configuration in the upstream tuyere zone. Focusing on single straight lance, six types of single lance configurations were designed by assembling four parameters in different ways. These four

Considering the variable cross section thickness of longitudinal profiled plate and the dynamic reductions of straightening rolls, an analytical model combining curvature integral method with linear decreasing straightening scheme was proposed to investigate the longitudinal profiled plate straightening process. Moreover, the calculation flow and solution algorithm of longitudinal profiled plate straightening

Through the solubility product theory of the ternary secondary phase, classical nucleation theory, and Ostwald ripening theory, a model was established to describe the thermodynamics and kinetics of (Ti, V)C precipitates in austenite/ferrite (γ/α) matrices. The model was used to calculate the volume fraction, precipitation–temperature–time (PTT) curve, and nucleation rate–temperature (NrT) curve of

A microstructural analysis was performed to determine the presence of oxygen in a wire rod section of AISI 1008 steel with a surface mechanical failure produced during wire drawing. The failure zone was analyzed by comparison using three different attack reagents: alkaline sodium chromate (ASC), ASC with hydrogen peroxide and amyl alcohol, and a solution of nitric acid in ethyl alcohol. The reagents

The high efficiency of Ce addition in grain refinement of δ-ferrite in a cast Fe–4 wt.%Si alloy was verified. In order to further understand the solute effect of Ce on the grain refinement of δ-ferrite, the conventional directional solidification technique, which enabled to freeze the solid–liquid interface to room temperature, was used to investigate the interfacial morphology and solute redistribution

A new approach for predicting forming limit curves (FLCs) at elevated temperatures was proposed herein. FLCs are often used to predict failure and determine the optimal forming parameters of automotive parts. First, a graphical method based on a modified maximum force criterion was applied to estimate the FLCs of 22MnB5 boron steel sheets at room temperature using various hardening laws. Subsequently

The quenching and partitioning steel is the representative of the third generation of advanced high-strength steel. The effect of quenching temperature on the microstructure and mechanical property of ferrite-containing quenching and partitioning steel was studied by intercritical annealing quenching and partitioning processes. When preparing a test steel with a tensile strength of 1300 MPa and total

Closing a single nozzle or multiple nozzles for a temporary casting operation (fewer strands casting) was common in a tundish due to insufficient molten steel or equipment failure. However, nozzle clogging usually happens under the situation of fewer strands casting. Hence, a temperature deviation index was introduced to characterize the temperature stratification of molten steel for a large capacity

Four Zn-rich Al–Zn–Mg–Cu alloys with different Mg and Cu contents were fabricated by spray deposition. The effects of Mg and Cu contents on the aging behaviors of the whole precipitation process of the alloys were systematically investigated. The results show that the primary precipitates in the under-aged and peak-aged alloys are GPII and η′ phases; no GPI zones were observed. During aging, the dissolution

The isothermal compression test for Ti–6Al–7Nb alloy was conducted by using Gleeble-3800 thermal simulator. The hot deformation behavior of Ti–6Al–7Nb alloy was investigated in the deformation temperature ranges of 940–1030 °C and the strain rate ranges of 0.001–10 s−1. Meanwhile, the activation energy of thermal deformation was computed. The results show that the flow stress of Ti–6Al–7Nb alloy increases

Two distinct regimes of strain rate sensitivity on yield strength are found in a high-strength nantwinned steel. The yield strength increases from 1410 to 1776 MPa when the strain rate increases from 10–3 to 1400 s−1. It is proposed from the measured small activation volume that the yielding of the nanotwinned steel at higher strain rates is governed by the dislocation bowing out from the carbon atmosphere

In the process of cold tandem rolling, chatter instability leads to serious impacts on enhancing rolling speed, improving product quality, reducing production cost and realizing intellectualization. Chatter occurs with the rolling speed up to a certain threshold value, but the critical speed is determined by both product specifications and rolling schedules. A 5-stand cold tandem rolling mill whose

Shaped Mg alloy foams with closed-cell structure are highly interested for a great potential to be utilized in the fields where weight reduction is urgently required. A powder metallurgical method, namely gas release reaction powder metallurgy route to fabricate Mg–X (X=Al, Zn or Cu) alloy foams, was summarized. The principles on shaped Mg–X foams fabrication via the route were proposed. In addition

2.25Cr–1Mo–0.25V base metal (BM) and welded metal (WM) with different temper embrittlement states were obtained by isothermal temper embrittlement test. The ductile–brittle transition temperature and the carbide size of temper embrittled 2.25Cr–1Mo–0.25V BM and WM increased with the isothermal tempering time. The increase in temper embrittlement time leads to a decrease in yield strength (YS) and ultimate

With the importance of the steelmaking industry in the economy and its negative impacts on the environment, reducing dust emissions is a vital focus in this field. Thus, the theory of dust generation in converter steelmaking process was analyzed and the influence of bottom blowing oxygen on dust generation was obtained through experimental research. The industrial test was carried out in a 120-t bottom

Heterogeneous nucleation is an effective way to promote the dispersion and precipitation of second-phase particles in steel and refine the grain size of the solidification structure. Not only refining as-cast structure grain size, but TiN in ferritic stainless steel can also pin grain boundaries and restrain the overgrowth of grains during rolling. The interface characteristics between TiN and heterogeneous

There are four types of Mg–Al–Si–O inclusions observed in the Mg-treated Al-deoxidized ultra-low-carbon steel containing trace Si, including SiO2, 2MgO·SiO2, 3Al2O3·2SiO2, and 2MgO·2Al2O3·5SiO2 and their composite inclusions. Using FactSage, the phase relationship of Mg–Al–Si–O system at 1473–2073 K was calculated using FactSage software, and the change in Si content can change the stable region range

During the solidification of high-alloy steel (0.4C–1.5Mn–2Cr–0.35Mo–1.5Ni), the high temperature gradient of solidified shell as well as the columnar crystal development would contribute to the centre segregation and cracking due to the high carbon and alloy contents. The effect of soft reduction process on the segregation of a 400 mm thick high-alloy steel slab was analysed. Industrial trials in

In order to understand the high-temperature deformation behaviour of alloy having hard surface layer, thermo-mechanically treated duplex stainless steel (DSS) is boronised for 0.75–6 h at 1223 K and subsequently deformed under compression mode at the same temperature under strain rate condition of 1 × 10−3, 2 × 10−4 and 6 × 10−5 s−1 until strain of 0.4. The substrate microstructure is almost isotropic

The effect of microstructures on strength, strain capacity and low temperature toughness of a micro-alloyed pipeline steel was elucidated. Five various dual-phase microstructures, namely, acicular ferrite and a small amount of (around 2 vol.%) polygonal ferrite (AF + PF), polygonal ferrite and bainite (PF + B), polygonal ferrite and martensite/austenite islands (PF + M/A), polygonal ferrite and martensite

The vacuum induction melting was adopted to fabricating Mg50−xTixNi45Al3Co2 (x = 0, 1, 2, 3, 4 at.%) composites protected by the high-purity helium atmosphere. Subsequently, the surface modification treatment of the as-cast alloys was carried out by mechanically coating nickel. The amorphous and nanocrystalline Mg50−xTixNi45Al3Co2 (x = 0–4) + 50 wt.% Ni hydrogen storing alloys as the negative materials

During a powder metallurgy process such as sintering, the primary role played by the atmosphere in furnace is to prevent an excessive oxidation of powder compacts in case of the formation of oxides as residuals on powder surfaces. In particular, the adjustment of furnace atmosphere is the key to eliminate the phenomenon “decarburization” likely to occur in carbon-containing compacts. A continuous belt

The significance of different deoxidation practises on the ductility and impact toughness of next generation of microalloyed heavy plates was elucidated to explore the best deoxidation practice in obtaining required mechanical properties, which was judged by the combined effects of composition, size and number density of inclusions on the ductility of the experimental high-strength low-alloy steel

A series of zinc oxide (ZnO) nanorods arrays with different morphologies are synthesized on stainless steel mesh via a facile electrodeposition method. The influences of electrodeposition parameters on the diameter, length, density and morphology of obtained ZnO nanorods are investigated systematically. The results indicate that the electrodeposition potential is the key factor for the morphology of

Microstructure and mechanical properties in core of a carburizing 20CrNi2MoV bearing steel subjected to cryogenic treatment were investigated. Conventional treatment sample was quenched and tempered at 180 °C for 2 h. Cryogenic treatment samples were quenched, cryogenically treated at − 80 and − 196 °C for 4 h, slowly returned to room temperature and thereafter tempered at 180 °C for 2 h, and finally

In order to research the effect of microalloying Nb, the microstructure and heat treatment distortion of case carburizing steels with and without Nb addition are compared. Results show that a uniform and fine prior austenite grain size was obtained for the steel with the addition of 0.03 wt.% Nb even after being carburized at 980 °C for 37 h, resulting in a very deep hardened layer of about 4 mm. Nb

High-/medium-entropy stainless alloys (HESAs/MESAs) are a new kind of alloys with great potential to combine excellent properties from high-/medium-entropy alloys (HEAs/MEAs) and stainless steels. A CrFeNi MESA was chosen to investigate its microstructures and mechanical behaviors. After homogenization, the strength and ductility of CrFeNi MESAs with single-phase face-centered-cubic (fcc) structure

The initial solidification process of microalloyed steels was simulated using a confocal scanning laser microscope, and the growth behavior of austenite grain was observed in situ. The method for measuring the initial austenite grain size was studied, and the M *0 (the parameter to describe the grain boundary migration) values at different cooling rates were then calculated using the initial austenite

The slab low-temperature reheating grain-oriented silicon steel was prepared in the laboratory, and the high-temperature annealing interruption tests were carried out. The effects of aluminum (which meant acid-soluble aluminum) on the grain size texture, precipitate, magnetic properties and their correlations were studied. The results showed that with the increase in aluminum element, the grain size

Dry centrifugal granulation (DCG) experiments for blast furnace slag (BFS) were performed by means of a rotary disk atomizer since water quenching method can create a series of problems. The results showed that the DCG method can granulate the BFS, but the results are easily affected by the slag flow rate, disk rotating speed, disk radius, disk material and slag falling height. The granulating parameters

The vacuum thermal evaporation technique was used to simultaneously deposit zinc coatings onto interstitial free steel plates and single-crystal silicon wafers in a high vacuum environment. The effect of substrate temperature on the morphology and crystal orientation of zinc coatings was investigated. When the substrate temperature was 25 and 50 °C, the zinc crystallites were plate-like and grew under

After applying torsion to cylindrical 304 stainless steel samples, a gradient structure along the radial direction was obtained. It was found that the volume fraction of α′-martensite increased gradually from the center to the surface of samples. The possibility of deformation-induced martensitic transformation was analyzed theoretically, whose conclusions were consistent with the experimental results

The microstructure evolution and the pitting corrosion resistance of a supermartensitic stainless steel after deep cryogenic treatment process were clarified through X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy (TEM) and electrochemical methods. The results showed that the microstructure of supermartensitic stainless steel mainly consisted of reversed

The design of high-strength steel has long been discussed in the field of metal structural materials. To further increase the strength of common high-strength steel and further decrease the cost for production, three direct-quench hot rolled steels were designed and fabricated. The rolling and coiling processes were set based on continuous cooling transformation curves. In addition, the effect of the

Bi2WO6 nanoplate/TiO2 nanowire and Bi2WO6 nanoflower/TiO2 nanowire composite films were successfully prepared using a hydrothermal method. The results show that the light absorption for Bi2WO6/TiO2 composite films is extended to the visible region after Bi2WO6 nanoplates and nanoflowers are assembled onto TiO2 nanowires. Furthermore, Bi2WO6 nanoflower/TiO2 nanowire composite film exhibits a better

The effect of quenching temperature and cooling conditions on the microstructure and mechanical properties of a 0.2%Nb medium chromium wear-resistant cast steel was investigated. The microstructure, carbides and volume fraction of retained austenite were characterized using the optical microscope, scanning electron microscope, transmission electron microscope and X-ray diffraction. The influence of

To improve the efficiency of the steelmaking process, a system of self-rotating lance was designed, and corresponding cold simulation mechanism was developed. The influence of the self-rotating lance on the mass transfer rate between slag and molten steel was investigated by comparing this novel system with the traditional oxygen lance. The results show that the self-rotating lance can stably rotate

Comparative analysis was conducted to illustrate the effect of high-temperature reduction pretreatment on the internal quality of 42CrMo casting billet. Analysis of macrostructure clarifies that reduction pretreatment could reduce the size of central cavities and equiaxed crystals and improve the segregation degree and porosity on statistics. Lath bainite matrix and granular structure on segregation

In recent years, the reformed coke oven gas (COG) was proposed to be used as reducing gas in a shaft furnace. A mathematical model of gas flow based on the reformed COG was built. The effects of the pressure ratio of reducing gas to cooling gas (k) on the gas distribution in the shaft furnace were investigated. The calculation results show that k is an important operation parameter, which can obviously

The microstructure–mechanical property relationship of a Cu-bearing low-carbon high-strength low-alloy steel, subjected to a novel multistage heat treatment including quenching (Q), lamellarization (L) and tempering (T), is presented. Yield strength of 989.5 MPa and average toughness at − 80 °C of 41 J were obtained in this steel after quenching and tempering (QT) heat treatments. Specimen QLT gained

Defect classification is the key task of a steel surface defect detection system. The current defect classification algorithms have not taken the feature noise into consideration. In order to reduce the adverse impact of feature noise, an anti-noise multi-class classification method was proposed for steel surface defects. On the one hand, a novel anti-noise support vector hyper-spheres (ASVHs) classifier

The effect of hydrogen addition on compression deformation behaviour of Ti–0.3Mo–0.8Ni alloy argon-arc welded joint has been investigated. Evolution mechanism of hydrogen-induced flow stress was discussed in detail. The results show that with increasing hydrogen content, the stretching and bending extent of fully lamellar microstructures including α lamellas and acicular hydride continued to increase

Precipitation strengthening of nano-scale TiC is a promising method to improve mechanical properties of Fe–16Mn–9Al–0.8C (wt.%) low-density steel. This work attempted to introduce nano-scale TiC precipitates by adding 1 wt.% Ti element. The experimental results show that these precipitates with the total fraction of about 2 vol.% were formed and no coarse precipitates were observed despite the high

To verify the microalloying function and segregation behavior of trace Mg at grain boundary in steel, the 2.25Cr–1Mo steel doped with 0.056% P containing different Mg contents was refined with a vacuum-induction furnace. The effects of trace Mg addition on the temper embrittlement susceptibility of 2.25Cr–1Mo steel were studied by step-cooling test and the segregation behavior of Mg at grain boundary

To solve the technical problems of hot metal desulfurization by injecting magnesium particulate, a new method of hot metal desulfurization by bottom-blowing magnesium vapor combined with mechanical agitation was put forward. The effects of three different desulfurization processes on the desulfurization efficiency were studied in view of thermodynamics and kinetics. It was found that the utilization

Fiber laser and gas metal arc hybrid welding of 440-MPa-grade high-strength marine steel was carried out at different welding speeds. The influence of welding speed on the microstructure and mechanical properties of weld metal was investigated. The weld-metal microstructure mainly consisted of pre-eutectoid ferrite, side-plate ferrite, acicular ferrite and lath bainite at a low welding speed. With

Least squares support vector machine (LS-SVM) plays an important role in steel surface defects classification because of its high speed. However, the defect samples obtained from the real production line may be noise. LS-SVM suffers from the poor classification performance in the classification stage when there are noise samples. Thus, in the classification stage, it is necessary to design an effective

The effect of the Al2O3 content and basicity (the molar ratio of MgO to SiO2) on the viscosity of a SiO2–MgO–FeO–Al2O3–CaO slag was studied to fully understand the smelting process of the ferronickel alloy. Experimental results show that the slag is a mixture of liquid and solid phases at the experimental temperature. The viscosity decreased as the basicity increased and increased as the Al2O3 content

The microstructure characteristics and properties (especially hole expansion property) of 800 MPa hot-rolled complex phase steel with different coiling temperatures were studied. The microstructure consisted of polygonal ferrite and precipitates when the steel was coiled at 550 °C, and when the steel was coiled between 460–520 °C, the microstructure was composed of granular bainite and martensite and