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

In cold rolling process, the flatness actuator efficiency is the basis of the flatness control system. The precision of flatness is determined by the setpoints of flatness actuators. In the presence of modeling uncertainties and unmodeled nonlinearities in rolling process, it is difficult to obtain efficiency factors and setpoints of flatness actuators accurately. Based on the production data, a method

Using the first-principles methods, the effects of different alloying elements M (M = Fe, Ni, Mn, Si, Mo, Cu, Y) on Cr2O3 with Cl adsorption are studied. The results show that the layer distance of all doped models has been widened to different degrees with Cl adsorption. When Mo or Y is doped into the passive film, the difference of layer distance is reduced to a certain extent. The interaction between

The inclined six-roll tube straightener is an important equipment for the finishing line. It can not only straighten the steel pipe, but also finish the ovality of the cross section. In the actual straightening process, the cross section of the tube is prone to deform, that is, the roundness is not good. The flattening displacement is an important parameter to control cross-section forming of tube

2205/Q235B clad steel plates were fabricated using a thermal simulator. The metallographic microscope, scanning electron microscope, energy-dispersive spectrometer, shear test, electrochemical corrosion test and acid immersion test were used to study the influence of the pass reduction ratio on the microstructure and properties of 2205/Q235B clad steel plate. The results show that the clad steel plates

Energy balances are a general fundamental approach for analyzing the heat requirements for metallurgical processes. The formulation of heat balance equations was involved by computing the various components of heat going in and coming out of the oxygen steelmaking furnace. The developed model was validated against the calculations of Healy and McBride. The overall heat losses that have not been analyzed

A 3D/2D hybrid multi-physical-field mathematical model, which takes into consideration the thermosolutal buoyance, was developed to predict the macrosegregation of gear steel 20CrMnTi continuously cast by a curved billet caster with size of 160 mm × 160 mm, and investigated the effect of final electromagnetic stirring (F-EMS) on the fluid flow, heat transfer and solute distribution in the liquid core

Composite coating on GH4169 alloy is prepared by laser cladding yttria-stabilized zirconia (YSZ)@Ni core–shell powders mixed with NiCoCrAlY alloy powders. The cyclic oxidation behavior of the coatings, especially the growth process of the oxide layer, is investigated based on experimental research and first-principle calculations. The results indicate that the oxidation resistance of coated GH4169

The influence of microstructural characteristics on Lüders strain and mechanical properties was explored by means of altering thermo-mechanical circumstances in an intercritical annealing (IA) medium-Mn Fe-11Mn-0.09C-0.25Si (wt.%) steel. By IA of cold-rolled samples with severe plastic deformation, exclusively equiaxed dual phases were obtained because of active recovery and recrystallization. The

Microstructural change, stress rupture property, deformation and fracture mechanisms of Nimonic 105 superalloy at 750 °C have been studied. Experimental results showed that the stress rupture strength of the alloy at 750 °C for 105 h is about 200 MPa. γ′ precipitates and M23C6 carbides grew gradually with prolonging the rupture time, while no significant change was observed in MC carbide morphology

The effects of inclusions on localized corrosion of Zr–Ti deoxidized low-alloy steels in marine environment were investigated by various analytical techniques including scanning electron microscopy with X-ray microanalysis (SEM/EDS), confocal Raman microscopy (CRM), and in situ scanning vibrating electrode technique (SVET). It was found that complex (Zr, Ti, Al)-Ox inclusions were responsible for the

Carbon dissolution from four types of metallurgical cokes and graphite was investigated by using immersion rods in a resistance furnace to clarify the influence of factors governing the rate of carbon dissolution from carbonaceous materials into Fe–Mn melts at 1550 °C. The factors studied were the microstructure of carbonaceous materials, roughness, porosity and the wettability between carbonaceous

Soft magnetic Co-based Co–Y–Nb–B bulk metallic glasses (BMGs) without Fe have been developed by micro-alloying Y and Nb into a Co75B25 alloy. First, addition of 3–4 at.% Y promotes the occurrence of glass transition and increases the supercooled liquid stability and magnetic softness. Co71.5Y3.5B25 metallic glass possesses a large supercooled liquid region (ΔTx) of 33 K and low coercivity (Hc) of 1

Molten slag is broken up by supersonic air into droplets through the air quenching dry slag granulation technique. The breakup process of blast furnace slag directly determines the droplet diameter and the waste heat recovery. In order to gain deep insight into the granulation mechanism and visualize the breakup process, three-dimensional unsteady numerical simulation based on the k-ω based shear stress

The properties of activated coke (AC) for sintering flue gas purification greatly affect the efficiency of desulfurization and denitration, but they gradually change during cycles. The change in properties of coal-based AC during cycles was studied to clarify the change law and AC optimization index. The AC oxygen content rapidly increases from 13.49 to 17.87 wt.% in the early cycles to form phenol

Helium ion irradiation at 350 °C was performed to study equilibrium segregation and radiation-induced segregation (RIS) of Cr at grain boundaries in reduced activation ferritic/martensitic steels. Cr concentration at grain boundary was measured by scanning transmission electron microscopy with an energy-dispersive spectrometer. The measured Cr concentration at grain boundaries in heat treated zone

To further improve the comprehensive properties of 42CrMo/Q235 laminated shafts produced by cross wedge rolling, the heat treatment of the shafts was studied. Tensile and bending tests were carried out to compare the changes in mechanical properties before and after heat treatment. The results showed that the interfacial bonding strength increased most after tempering at 350 °C for 45 min. The microstructure

The O2–CaO jet with shrouding combustion flame demonstrates some advantages in quick melting and effective slag foaming by delivering lime powder deeply into the molten bath. Combining the discrete particle model and the eddy dissipation concept model with the detailed chemical kinetic mechanisms (GRI-Mech 3.0), computational fluid dynamics models of the O2–CaO jet with different shrouding fuel mediums

A mathematical model based on the computational fluid dynamics method, heat and mass transfer in porous media and the unreacted shrinking core model for the oxidation reaction of an individual magnetite pellet during preheating was established. The commercial software COMSOL Multiphysics was used to simulate the change in the oxidation degree of the pellet at different temperatures and oxygen concentrations

Scanning electron microscopy, X-ray diffraction, a neutral salt spray test, and electrochemical methods were applied to observe the microstructure and test the corrosion resistance of hot-dip galvanized steel before and after the addition of La and Ce. La/Ce mixture existed in the form of (La, Ce)Zn13 on the coated surface, decreased the coating thickness and accelerated the zinc dendritic growth.

The microstructure transformation and precipitation behavior of nano-carbides in Ti microalloyed steel during isothermal process were studied by a compression test on a Gleeble 3800 thermomechanical simulator and analyzed by optical microscopy, transmission electron microscopy and other methods. The results show that γ → α phase transformation and TiC precipitation take place in Ti microalloyed steel

The combustion properties and grindability of Shenmu low-rank coal (SM) and its four different semi-cokes were studied by the self-designed equipment and Hardgrove method. The four semi-cokes were obtained under the pyrolysis temperature of 400, 500, 600 and 700 °C, named as SM-400, SM-500, SM-600 and SM-700, respectively. The analyses of nitrogen adsorption, Fourier-transform infrared spectroscopy

The wear tests of titanium matrix composites (TMCs) at the loads of 50, 100, 120, and 150 N were carried out with an MMW-1 vertical universal friction and wear tester to study the addition of multilayer graphene (MLG)/nano-Fe2O3 composites (0, 0.1, 0.2, 0.3, 0.4, and 0.5 g) on the dry sliding wear behavior of TMCs. TMCs presented a marked variation in wear loss as a function of the amount of MLG/Fe2O3

Friction stir spot welding was successfully applied to the 1.2-mm-thick DH590 dual-phase steel plates by using a polycrystalline cubic boron nitride rotating tool. During welding, the rotation speed ranged from 600 to 1000 r/min and the penetration depth ranged from 0.1 to 0.3 mm. In the spot joints, the size of the stir zone increased with the increase in rotation speed as well as the penetration

Ti-stabilized 321 stainless steel was prepared using an electric arc furnace, argon oxygen decarburization (AOD) furnace, ladle furnace (LF), and continuous casting processes. In addition, the effect of refining process and utilization of different slags on the evolution of inclusions, titanium yield, and oxygen content was systematically investigated by experimental and thermodynamic analysis. The

The ratcheting response of 316 stainless steel samples at the vicinity of notch roots under single- and multi-step loading conditions is evaluated. Multi-step tests were conducted to examine local ratcheting at different low–high–high and high–low–low loading sequences. The stress levels over loading steps and their sequences highly influenced ratcheting magnitude and rate. The change of stress level

Based on the chemical composition of traditional hot-stamped steel (e.g., 22MnB5 and 30MnB5), Nb and V microalloying elements are added into 30MnB5 steel to meet the requirements of ultra-high strength, excellent ductility and potent resistance to hydrogen embrittlement (HE) at the same time. The influence of hot-stamped steel on HE was studied by conducting a hydrogen permeation method and pre-charged

The recycling of scrap has attracted more attention in recent years, and scrap can be used as iron-bearing material to smelt hot metal. The smelting practice of blast furnace (BF) with scrap addition in China was investigated, with the types of scrap being small pieces of scrap, such as crushed materials, light and thin materials, and small compacts which were easy to be added into BFs. The higher

The effects of corrosion temperature, oxygen flow rate and corrosion time on the transformation of metallic iron were systematically studied, and the effects of mineral phases of Fe-bearing products on Ti–Fe separation were investigated. The reaction mechanism of metallic iron in corrosion process was proposed. The results showed that corrosion temperature played a key role in determining the transformation

High-temperature fatigue property of Ni-based GH4720Li superalloy at 550 °C has been investigated at maximum strain from 0.8% to 1.1%. Microstructural characterization and oxidation behavior of superalloy during high-temperature fatigue have been analyzed by transmission electron microscopy and scanning transmission electron microscopy. The results show that a stable response following a slight cyclic

The gasification reactivity and kinetic parameters of coal chars for non-isothermal steam gasification were investigated. One kind of lignite and three kinds of bituminous coals were used as the samples, and their coal ranks follow the ascending order: XB < KL < ZJ < GD. As characterized by the comprehensive gasification index, the gasification reactivity of coal chars follows the descending order:

It is of great significance to investigate effect of multiple heat treatments on fracture property of centrifugal casting stainless steels Z3CN20.09M cut from pump casing with long-term thermal aging degradation for nuclear power plants to consider actual operation of nuclear power plants. Both multiple heat treatments and accelerated thermal aging experiment at the same temperature of 400 °C for different

To improve the hydrogenation and dehydrogenation dynamics of NdMg12-type alloy, we replaced part of Mg with Ni in the samples and used the ball milling method to prepare NdMg11Ni + x wt.% Ni (x = 100, 200) samples. The influences of milling duration and Ni content on the electrochemical and gaseous dynamics of the samples were studied in detail. Dehydrogenation activation energies of samples were calculated

There have been many studies on three-dimensional (3D) printing using metal compounds. However, 3D printing using a metal compound has disadvantages in that it increases the cost for supplying metal materials. A method of using slag which is a recyclable material has been proposed to reduce costs. With the growing demand for additive manufacturing using by-products, slag has gained attention as a diverse

A new method was presented to inhibit bulging deformation and fluctuation of free surface by magnetic pressure. A research combined with numerical and experimental methods was conducted to investigate the feasibility and inhibition efficiency. The parameters including magnetic flux density, frequency and action area of magnetic pressure were analyzed. The results show that the method is feasible, and

Dephosphorisation basic oxygen furnaces (deP-BOFs) greatly differ from conventional BOFs in the melting process, especially its many limits on adding scrap. A mathematical model of the steel scrap melting process was established in MATLAB to investigate the mechanism of scrap melting in deP-BOF in terms of coupling effects of the carbon content of the molten steel, temperature, scrap preheating and

The determination of the local cooling rate has a great significance in optimizing the parameters of electroslag remelting (ESR) and improving the quality of the ingots. An innovative method was proposed for calibrating the local cooling rate of M42 high-speed steel (HSS) in the ESR process. After resolidification at different cooling rates under high-temperature laser confocal microscopy, the carbide

In situ (TiC + SiC) particles (5 vol.% and 10 vol.%, respectively)-reinforced FeCrCoNi high entropy alloy matrix composites were fabricated via vacuum inductive melting method, with equal volume fractions of TiC and SiC particles. X-ray diffraction, scanning electron microscope and energy diffraction spectrum were employed to analyze the microstructure and composition of the samples. The results manifested

H13-mod steel developed after optimizing the composition and heat treatment process exhibits good hardness and impact toughness and can be used as a shield machine hob. Based on the Avrami equation, the dynamic recrystallization (DRX) behaviour of H13-mod steel during hot compression was studied in the temperature of 900–1150 °C and strain rate ranges of 0.01–10 s−1. A DRX model and finite element

Al0.5Cr0.9FeNi2.5Vx (x = 0, 0.2, 0.4, 0.6, 0.8, 1.0) multi-principal alloys were prepared by vacuum arc melting. The effect of vanadium addition on its microstructure and properties was investigated. The results show that the alloys of all components exhibited an FCC single-phase structure. With the addition of vanadium, the microstructure of the alloy changed from dendrites to equiaxed crystals, the

The surface oxide layer of grain-oriented electrical steels was investigated by scanning electron microscopy. The formation mechanism and the influence on the glass film of the surface oxide layer were analyzed by the calculation of thermodynamics and kinetics. The surface oxide layer with 2.3 μm in thickness is mainly composed of SiO2, a small amount of FeO and Fe2SiO4. During the formation of surface

Quenching and partitioning (Q&P) heat treatments with different annealing temperatures and fixed initial quenching temperatures were applied to cold-rolled low-carbon steel with the initial microstructure of ferrite and pearlite, aiming to gain the same amount of austenite (preset value) before the partitioning stage. The chemical compositions of the material have been specially designed, containing

Gradient microstructure of the specimen was achieved by applying gradient thermoplastic deformation via electric resistance heating and hot compression of the cone-shaped specimen. A numerical modeling and experiment tests are conducted to investigate the microstructure evolution and mechanical properties in different regions of the specimen subjected to the gradient process parameters. Microstructure

The constitutive relationship is the basis for studying the material processing technology and controlling the quality of products. Data and models of the plastic flow behavior of materials are often required during the manufacturing process. Therefore, establishing constitutive models with high precision and generalization and enriching material database is of great significance for optimizing processing

Highly reactive ferro-coke has been widely studied due to its contribution to the energy saving and emission reduction in blast furnace ironmaking. To optimize the coking process of ferro-coke and improve its metallurgical properties, it is necessary to clarify the influence of initial iron ore on the strength, micro-morphology and CO2 gasification reaction behavior of formed ferro-coke. The effects

The effect of dew points (− 50, − 10 and + 10 °C) on the galvanizing properties of a high-manganese twinning-induced plasticity (TWIP) steel was studied. Scanning electron microscopy (SEM), glow discharge optical emission spectrometry (GDOES) and X-ray photoelectron spectroscopy (XPS) were used for microscopic observation and qualitative analysis of the interfacial layer between the steel surface and

The Standard Test Methods for Tension Testing of Metallic Materials (ASTM E8) mandates a specimen gauge reduction for obtaining the tensile properties of reinforcing steel bars. The standard outlines the specimen preparation requirements and methods to ensure that test results well represent the material properties. On the other hand, some codes differ regarding the approach to specimen preparation

Electrical additive manufacturing can improve manufacturing efficiency and reduce the cost of 16MND5 reactor pressure vessel steel. Impact tests were conducted to compare the impact toughness of 16MND5 steels manufactured by the electrical additive manufacturing and conventional forging, respectively. It is found that the impact toughness of electrical additive manufacturing specimen was slightly higher

To realize cross-wedge rolling of shaft parts without a stub bar in a short process, an axial closed–open-type cross-wedge rolling technique was proposed. Based on the strain characteristics in the rolling, evaluation indices of deformation uniformity were provided, and the DEFORM-3D software was adopted to conduct numerical simulations of the rolling process. The metal flow and strain distribution

Grain boundary of α phase damaged ductility of laser melting-deposited TC18 titanium alloy and grain boundary of α phases were difficult to break by nominal heat treatment. An extra thermal deformation was introduced to break the grain boundary of α phase with the improved mechanical property of TC18 titanium alloy fabricated by laser melting deposition technique. Results indicated that after thermal

To prepare ultra-high-yield strength twinning-induced plasticity (TWIP) steel and reveal its work hardening mechanism at different strain rates from the microcosmic range, the microstructure evolution mechanism of Fe–20Mn–0.6C TWIP steel was investigated at strain rates of 10−4–103 s−1 using a high-speed tensile testing machine and a transmission electron microscope. The results show that the strain

The prediction of the mechanical properties of hot-rolled strips is a very complex, highly dimensional and nonlinear problem, and the published models might lack reliability, practicability and generalization. Thus, a new model was proposed for predicting the mechanical properties of hot-rolled strips by deep learning. First, the one-dimensional numerical data were transformed into two-dimensional

The denitrification rate of the cross-flow activated coke flue gas purification facility varies with operational parameters. According to the simulated experiments, the denitrification rate with the height drop of the denitrification unit experiences 100%, rapid decreasing, and gradual rising to the equilibrium. According to the correlation analysis results based on production data, several operational

Gas-quenched steel slag abrasive was obtained by gas quenching with high-temperature liquid steel slag as raw material. The phase composition, thermal properties, micromorphology, magnetic properties, and mechanical properties of the particles were characterized by using an X-ray diffractometer, a differential thermal analyzer, a scanning electron microscope, a magnetic property meter, and a compressive

Aluminum alloy 6061 and high-strength steel Q460 were joined by laser-arc-adhesive hybrid welding technology successfully. A Cu alloy interlayer was added between Al alloy and high-strength steel. The effect of the adhesive on laser-arc-adhesive hybrid welding of Al alloy to high-strength steel was discussed. The optical microscope, scanning electron microscope and electron probe micro-analysis were

Stainless steel (SS) 410 is widely used in many components of nuclear reactors due to its good corrosion resistance and high strength. However, wear is a major issue of these components due to its continuous sliding. SS 420 and Colmonoy 5 particles were deposited over SS 410 substrate by laser cladding process. Then, X-ray diffraction was used to find the phases present after cladding process. Further

The adhesion of fine iron ore particles during fluidized bed reduction was studied using pressurized visible fluidized bed laboratory equipment. The results showed that the optimal operating parameters for pure hydrogen reduction under high pressure were reduction temperature of 1073 K, particle size of 0.18–0.66 mm, pure H2 linear velocity of 0.8 m/s, reduction pressure of 200 kPa, and reduction time

Thermodynamic theory was used to calculate the formation temperature and site fraction of MC carbides in Fe–C–Ni–V–Ti system. The calculation results showed the theoretical formation conditions of core–shell MC carbides. One-step and two-step heat treatment processes were used in Fe–C–Ni–V–Ti alloy to, respectively, obtain homogeneous and core–shell MC carbides, which was consistent with the thermodynamic