A vertical layered cooling process is developed to get more uniform cooling and higher heat transfer efficiency when compared with the circular-type and vertical integrated sinter cooling processes in this work, which has been demonstrated by the example. Based on the vertical layered cooling process, the maximum temperature of the cooled sinter and the minimum waste heat recovery is treated as two

Continuous cooling transformation (CCT) diagrams of undeformed and 40% compressively deformed pearlite heat-resistant steels at 950°C were obtained by a combined method of dilatometry and metallography. The microstructure and hardness of the steel under these two experimental conditions were compared and analysed. The effects of austenite deformation on the CCT of pearlite heat-resistant steel are

The recent progress and development of ironmaking in China as of 2019 was introduced. China has achieved a remarkable progress in eliminating outdated production capacity of steel industry, accomplishing the upper limit target ahead of schedule to reduce production capacity by 150 million tons during the thirteenth Five-Year plan. The blast furnaces are gradually forming a four-element burden structure

ABSTRACT Physicochemical behaviour of the pellets, sinters and its mixture (60% pellets: 40% sinter) is investigated by a series of smelting and quenching experiments. For all ferrous raw-material beds, three distinct stages of bed shrinkage occur due to indirect reduction, softening and melting. However, the characteristic nature (displacement, temperature and permeability) differ with the ferrous

(2020). Steel World editorial 2020. Ironmaking & Steelmaking: Vol. 47, No. 5, pp. 459-459.

Interstitial free (IF) grade steels have high transformation temperatures and often results in non-uniform rolling and lower yields. In the present work, industrial ferritic rolling process is developed, where finish rolling is carried out below the Ar1 temperature for the IF grade steel. Offline simulation was carried out using a hot strip mill model (HSMM) software and full-scale ferritic rolling

The effect of Al content on the characteristics and formation of inclusions in the light-weight Fe–5Mn–xAl steels was investigated in this study. Four synthetic steels with different Al content were produced in the laboratory. The types of observed inclusions were Al2O3(pure), Al2O3–MnS, AlN(pure), AlN–MnS, AlON–MnS, AlON and MnS. Increasing Al content from 0.5% to 6% increased the total amount of

To discussed the influence of reheating and cooling on the crack initiation mechanism under the hot cycle mode of a continuous casting slab, during thermal cycling and analysed the relationship between the lower grain size and the crack initiation toughness under different temperature fluctuations. A thermal expansion tester and a Gleeble-3500 thermodynamical simulator were used to perform thermal

Based on particle image velocimetry (PIV) technology, the process and flow field characteristics of slag entrapment under the condition of critical slag entrapment are investigated by water model. The change of interface flow field at the slag entrapment process from the occurrence to end of critical slag entrapment is analysed, and the influence of kinematic viscosity of slag on critical slag entrapment

Control of slab camber is an important topic in hot strip rough rolling process. In this study, a slab camber control system, composed by a camber prediction model and a gap levelling value calculation model, based on the Takagi–Sugeno (T–S) fuzzy model is proposed. The performance of the developed camber prediction model is evaluated by the estimation error between the predicted and measured values

A comparative study to assess the abrasive wear performance of steels for concrete mixing drum, coiled at different temperatures, was conducted by MLS-225 wet sand/rubber wheel abrasion wear tester. The microstructures and mechanical properties of tested steels before and after wear tests were examined by the optical and scanning electron microscopes, electron backscatter diffraction, Vickers hardness

To effectively recycle the phosphorus in P-bearing steelmaking slag and use it as slag phosphate fertilizer, it is necessary to study the effect of slag temperature on occurrence forms and enrichment behaviour of phosphorus in P-bearing steelmaking slag. In this work, the thermodynamic and kinetic behaviours of the formation of phosphorus-rich phases are systematically investigated. The results show

A new process has been developed for inclusion removal. This process involves the creation and dispersion of fine bubbles in molten steel by calcium carbonate powder injection through the nozzles of the up-snorkel in RH (Ruhstahl Hausen Process) degasser. The plant trials have been carried out in ANSTEEL and the ruling factors have been analysed. The results indicate that this novel technique is beneficial

The blast furnace gas separated by a membrane has a higher content of combustible components. In order to explore its secondary utilization in blast furnace production, numerical simulation is conducted by means of Fluent software, and the model is verified by experimental data. Results show that when the blast furnace gas separated by the membrane is used as pulverized coal carrier gas for blast furnace

Lime magnetite pellets (LMPs) containing CWF phase (CaFe3O5) provide potential feed materials for ironmaking. In this paper, the effects of typical impurity oxides inherent to magnetite ores such as Al2O3, MgO and SiO2 on the formation of CWF in LMPs have been investigated. The thermodynamics of the Ca–Fe–O–X systems (X = Al, Mg or Si) were assessed followed by time-series experiments using natural

The physical and mechanical properties of iron ore agglomerates are highly dependent on their chemical, mineralogical and microstructural properties. The effect of Al2O3, MgO and SiO2 on the phases generated during the reaction of lime magnetite pellets (LMPs) were presented in Part-I of the current study. In this Part II study, a detailed chemical and microstructural analysis is presented in order

The precipitation and corrosion behaviour of Fe–19Cr–1.6Ni–0.9Mo–0.2N–xMn duplex stainless steel was investigated aging at 800°C. With more Mn addition, the precipitation changed from χ-phase to σ-phase by prolonging aging time to 54 h, and the accelerating of aging induced σ-phase precipitate is mainly due to its partition by Mn. The addition of Mn from 3.6 to 5.5 wt-% decreased pitting corrosion

Magnesium aluminate spinel (MA spinel) refractory samples were prepared and their cold and hot modulus of rupture, thermal shock resistance were determined, phase composition and microstructure were analyzed by means of XRD and SEM. Experimental results showed that: with introduction of MgO aggregates modified by α-Al2O3 ultrafine powder coating approach, considerable amount of well-developed spinel

High efficiency and clean emission operation of a blast furnace are mainly determined by its operating stability, which is closely related to the position of the cohesive zone (CZ) in the blast furnace. In order to monitor the CZ position in real time, a prediction model of the CZ was proposed by combining an off-line computational fluid dynamics (CFD) calculation and support vector machine (SVM) modelling

Desulphurization is essential in the steelmaking process for high-quality steel production, and sulphide capacity has proven to be an effective index to evaluate the desulphurization ability of molten slag or flux. Several analytical or empirical models have been proposed to calculate the sulphide capacity. However, these models usually show insufficient generalization ability when new variables/data

Twin-roll strip cast-rolling is a frontier process which produces a metallic strip directly from the melt. The main idea behind the presented research is to develop a new type of sectional roll surface heat transfer boundary condition. On this basis, a numerical simulation model of heat-flow coupling considering solidification was established to support the new boundary condition (BC). Finally, the

An image analysis-based method is developed to automatically interpret videos of a transparent Hele-Shaw model in studies of blast furnace hearth drainage in pilot scale. By the approach, information from experiments can be extracted for quantitative assessment of the draining phenomena. The algorithm consists of modules for (1) image pre-processing, (2) interface tracking, and (3) bending-point detection

The aim of this work was to derive new quality criteria based on steel composition and cooling pattern for continuous casting and for the subsequent cooling and reheating processes. The criteria were devised based on the outputs of multiphysics simulation tools for casting applications. The criteria were found to be good predictors of whether a steel grade combined with a given cooling pattern is prone

During the converter steelmaking process, with an increase in the furnace life, the bottom blowing components will have different degrees of blockage. In this study, water model and numerical simulation experiments were performed to study the influence of the non-uniform bottom blowing gas supply mode on the dynamic properties of molten bath in a 300t converter. The results show that under the non-uniform

Mathematical models appear as very attractive alternatives in blast furnace studies. Therefore, a three-dimensional model is described and validated to simulate the flow and combustion of binary coal blends under simplified blast furnace conditions. The present article aims to analyse the performance of different coals and their blends for conventional and coaxial oxygen enrichment methods. Among the

The effect of Ce on the hot-working ability of lean duplex stainless steel (LDSS) was investigated in this paper. A hot tensile test was performed by GLEEBLE 3500 to compare the high-temperature deformation behaviour of materials containing 0.01% Ce and no rare earth added. The results show that Ce significantly promoted LDSS recrystallization at a strain rate of ε˙ = 1 × 10−3 s−1, softening austenite

A CDF model for simulating gas dynamics, heat and mass transfer in the freeboard of a pilot-scale Rotary Hearth Furnace (RHF) is developed in conjunction with an independent solid reduction model at the bottom of the hearth. The effect of air-inlet configuration and inlet fuel composition on the fuel requirement, exit gas composition, fluid flow, temperature, and gaseous composition distribution have

Industrial trials and thermodynamic analysis were performed to investigate the transient influence of cerium on inclusions in an Al-killed non-oriented electrical steel. Inclusions were statistically analyzed using an automatic scanning electron microscope. Without cerium addition, inclusions in the molten steel were predominately MgO·Al2O3 ones as well as a small number of Al2O3–MgO–CaO ones, and

Increase in global electrification is driving the development of new electrical steels with improved performance, such as Fe–6Si suitable for high-frequency e-machines. Fe–6Si steel is difficult to cast and roll such that currently, the only commercial production is via downstream siliconisation to increase Si content. This paper explores the feasibility of casting ultra-high silicon electrical steels

Energy optimizing furnace (EOF) is a primary steel making reactor, where the autogenous exothermic reaction heat, associated with the solute oxidation is utilized for making the steel. The thermo-kinetic reactions of the steel making process have been evaluated in the world’s largest, 65 ton EOF, at JSW Steel Ltd., Salem. The solute oxidation as a function of blow time and Si content was evaluated

The mechanical properties of steel depend strongly on chemical composition and the parameters used during thermomechanical processing. Understanding how each variable affects such properties is indispensable for obtaining high-quality steel products at a lower cost. However, the large number of variables involved in the manufacturing process makes this a difficult task. It is possible to use statistical

Cuspidine is an important crystallization product in CaO–SiO2–CaF2 based mould flux. A deeper understanding of cuspidine crystallization behaviour is significant to obtain superior heat transfer and lubricative properties. Cuspidine crystallization was observed in situ using a confocal scanning laser microscopy. The results shown that cuspidine typically shows different dendritic morphologies in molten

The ever-increasing pressure on the steelmaking industry to reduce its environmental footprint and achieve higher performance ispushing the sector to continuous improvement of its processes, This new paradigm places steel scrap recycling-based manufacturingprocesses as one of the main alternatives for the steelmaking industry. Using heterogeneous recycled scrap mixtures for producing new andhigher

ABSTRACT To lower the iron losses of the hot metal desulphurisation (HMD) process, slag modifiers can be added to the slag. Slag modifiers decrease the apparent viscosity of the HMD slag. Most common slag modifiers in industry contain fluoride as a fluidiser. However, fluoride leads to a higher magnesium consumption and has health, safety and environment issues. Fluoride-free alternatives like nepheline

In this paper, the industrial experiment of bottom-blowing O2–CaO was carried out by using a mixed injection of multi-gas medium to reduce the erosion of bottom-blown components and improve the life of the converter. The mechanism of slagging and dephosphorization during the process of bottom-blowing O2–CaO was deeply studied, a better way of slag making by blowing CaO powder from the bottom of the

In this work, the influence of original microstructure on wear property of ER9 wheel steel is studied by GPM-40 rolling wear tester. The pearlite + proeutectoid ferrite (P+F) sample exhibits the lower wear loss than the tempered sorbite (TS) sample at different cycles. However, the TS sample has better fatigue wear resistance than the P+F sample. High wear loss and more uniform plastic deformation

To obtain solid inclusions in LF refining process, the influence of silicon content in steel on compositions of inclusions during LF refining were investigated in Al-killed steel. Influence of silicon on compositions of inclusions was found to be great. The [Ca] content of steel was supplied from the reaction of [Al] and CaO. The [Si] content affected the [Ca] content by the reaction (SiO2) + 2[Ca]→[Si]+2(CaO)

The effect of Nb on the dissolution and precipitation behaviours of the network carbide in bearing steel, including the precipitation and dissolution temperature and the thickness of network carbide has been investigated in this paper. The precipitation and dissolution processes were carefully compared and analysed in bearing steels with different contents of Nb. The results showed that the presence

Fluid flow is of great importance to the quality of near-net-shape beam blanks. Particle image velocimetry (PIV) was employed to measure the fluid flow inside a full-scale water model for a beam blank continuous casting mould from five sections under the different submerged entry nozzles (SENs) in the present work. The results show that the jet flow under the single-port SEN leads to a too significant

The present work was carried out to study the evaporation of fluoride from CaF2–CaO–Al2O3–MgO–Li2O–(TiO2) slag with different TiO2 contents. The evaporation ratio is determined by monitoring the weight change of the slag by isothermal thermogravimetric analysis in the temperature range of 1470–1530°C. The results show that the evaporation ratio of fluoride is promoted by increasing temperature and

Aiming at the high-efficiency utilization of vanadium–titanium magnetite with high chromium content, a slag formation path in the converter smelting process of semi-steel containing chromium was proposed. The influences of MnO and Cr2O3 on the melting characteristics of converter slag were calculated through FactSage. The effects of components and temperature on the equilibrium distribution ratio of

This paper presents optimum operating parameters for the production of thin strips of 40 mm in width and ∼4 mm in thickness of Fe–17%Mn–4%Al–3%Si–0.45%C wt-% TWIP (TWinning Induced Plasticity) steel using the present version of the Horizontal Single Belt Casting (HSBC) process. A two-dimensional model was developed to examine the flow of molten metal in the HSBC process, primarily focusing on investigating

Ferrite/martensite dual-phase steel is indispensable for manufacturing different automobile parts. In the present study, uniaxial tension tests and metallographic analyses are performed to reveal the fracture evolution in ferrite/martensite dual-phase flange steel with a high hole-expansion ratio. The results indicate that in the ferrite/martensite dual-phase steel, cracks originate at the interface

Experiments on flow field and heat transfer were carried out to quantitatively analyse the performance of an air-atomized cooling nozzle. A heat transfer platform and a particle image velocimetry system were applied to study the spray characteristics of the nozzle. The effects of water pressure and air pressure on flow rate, spray angle, water flow density and droplets velocity were investigated. The

Mullite brick is one of the most extensively utilized blast furnace hearth lining materials that feature several advantageous properties. In this study, the microstructure and physical properties of a mullite brick under different thermal treatment temperatures were investigated. The results showed that the temperature could not influence the micro-morphology of the mullite aggregate, but it directly

Mass balances provide a fundamental approach for analysing the oxygen steelmaking process. Steelmaking plants commonly have in-house mass balance models for controlling process parameters. However, there exist only a few details in the literature pertaining to the formulation of such models. Recent research published by Urban et al. [1] surveyed more than 30 BOF around the world and found that the

This research aims to investigate the influence of the slag basicity from 1.40 to 1.83 on dephosphorization of the hot metal with a CaO–FeO–SiO2–MgO–Al2O3 molten slag at the low temperature of 1653 K. The results indicated that the dephosphorization ratio was increased with the increase of basicity. Even at the low basicities of 1.73 and 1.83, the dephosphorization ratios can be as high as 77.3 and

The article presents the results of experimental studies of the features of forming the side surface and the crystallization structure of steel ingots, produced by the method of electroslag remelting with a layer-by-layer formation. The ingots with diameters of 160 and 220 mm were produced by remelting consumable electrodes in a pulsed mode, providing the periodicity of the processes of electrode melting

In this study, the possible reason for conveying problems sometimes observed in the pneumatic transport of casting powders from the storage containers to the mould was studied. Since some correlation in the occurrence of the said conveying problems to days with high humidity has been observed, the influence of the relative humidity of the air on the flowability of casting powders was investigated.

In order to overcome the environmental pollution caused by traditional water-quenching slag treatment and recover a large number of waste heat from blast furnace slag (BFS), the dry granulation process had attracted more and more attention, in which the granulation process was the key. The slag granulation and the crystallization mechanism of the BFS were studied, and the hot experimental results were

In oxygen steelmaking, one important aspect is to depict the splashing induced by the impingement of multiple jets quantitatively. In this paper, experiments were conducted to investigate the splash sheets. The results demonstrated that with the decrease of lance height, the sheet area increased, while the sheet height decreased. The sheet diameter was much less affected by the gas flow rate compared

This study presents an effective and cleaner process with hydrogen-rich gases that uses oxidation roasting followed by gas-based direct reduction and melting separation to recovery iron, titanium, vanadium, and chromium from Hongge vanadium titanomagnetite (HVTM). The process parameters were systematically investigated and determined to be roasting temperature at 1200°C, roasting time of 15 min, reduction

Industrial experiments and thermodynamic calculations were performed to investigate the evolution of non-metallic inclusions during cooling and solidification of GCr15 bearing steels with different steel compositions. Non-metallic inclusions in bloom and rolled rod were characterized using the improved non-aqueous electrolysis method firstly. Inclusions in molten steel were mainly irregular MgO·Al2O3

The influence of anthracite unburned pulverized coal (AUPC) on the properties of coke at high temperature was studied using the thermogravimetric equipment. The micro morphology and mineral transformation were analyzed by scanning electron microscope with energy spectrum (SEM-EDS) and X-Ray diffracton (XRD) in present research. The results show that CO2 preferentially reacts with AUPC, making SiC easier

Prototype parts can be produced rapidly and at low cost using the incremental forming method. The most important problem with this method is that it causes undesirable variations in wall thickness. Various methods have been developed to improve the wall thickness distribution of the part resulting from forming. One of these techniques, the rolling blank holder (TPIF-RL) method, was used in this study

Alkali metal circulation enrichment occurs in blast furnaces, which is harmful to the blast furnace. The amount of enrichment helps to quantify the effect of alkali metals on blast furnace production, but it is not possible to directly measure the actual alkali metal enrichment in blast furnaces for technical reasons. On the basis of a thermodynamic model, FactSage was used to calculate the effects

The stability of the blast furnace (BF) process depends on the quality of raw materials charged into the BF. Apart from various process variables, slag viscosity and slag fluidity are key parameters that require due attention for the stable BF operation. The varying Al2O3 content in slag increases the viscosity of slag and thus hinders the separation of slag from hot metal during the casting process

The continuous steel casting process is characterised by physico-chemical phenomena that are considered in the macro- and microscale. This paper attempts to assess the impact of local changes in the hydrodynamics of liquid steel flow in a one-strand slab tundish on the behaviour of the alloy addition, and consequently, the chemical homogenisation of the liquid steel entering the mould. Four variants

An artificial neural network model is used to predict high-temperature ductility of steels from their composition and thermal history. The model used literature data on reduction of area (RA). In most types of steel, RA has a U-shaped or V-shaped function of temperature; this shape was represented using a Gaussian fit. The predictive model considers conditions, including alloy composition and thermal

The Si content in pig iron is one of the important indicators for evaluating the technical level of ironmaking in the blast furnace. From the late twentieth century, the production of low-Si pig iron has attracted more and more attention in steel industries of the world. For ironmaking process, the decrease of Si content is beneficial for increasing the coefficient of utilization of the capacity of