Materials Processing Fundamentals: Poster Session
Sponsored by: TMS Extraction and Processing Division, TMS: Process Technology and Modeling Committee
Program Organizers: Antoine Allanore, Massachusetts Institute of Technology; Jonghyun Lee, Iowa State University; Guillaume Lambotte, Boston Electromet
Monday 6:00 PM
February 27, 2017
Room: Hall B1
Location: San Diego Convention Ctr
E-53: Control of Low Melting Point MnO-SiO2-Al2O3 Inclusions in Low Carbon Thin-strip Continuous Casting Steel: Jing Chen1; 1Shanghai University
There is magnificant difference in the demand for molten steel quality between thin-strip continuous casting and traditional continuous casting. In order to make sure the high surface quality of product, to generate an oxidation film on the surface of cooling roller is required. This will require that the high level of oxygen content in molten steel and inclusion with low melting point. So the control of inclusion content is the key factor. In this article, the probability of production of low-melting inclusion which is mainly consisted of SiO2 and MnO is studied by controlling the initial oxygen level and addition order of deoxidization product. The interaction concentration (activity) between each element in the ternary system of Al2O3-SiO2-MnO is obtained by SELF-SreM3 model. The equal [Mn], [Si], [O], [Al] curve under the temperature of 1823K and equilibrium condition in ternary system of Al2O3-SiO2-MnO is obtained by relative thermodynamic calculation as well.
E-54: Effect of Modeling Flows on Mixing Time in 40t Ladle with Bottom Gas Blowing Process: Le Wang1; Liu Liu1; Bingji Yan2; 1Central Iron and Steel Research; 2Soochow University School of Iron and Steel
Base on the generalized similarity principle, water model experiments had been conducted to investigate mixing phenomena of argon injection from the ladle bottom with eight types of tuyere arrangement. In this research, the harmonic number(H0) was considered as an evaluating indicator and four variables were mainly investigated, which were the blowing position, aspect ratio, Froude number and gas flowrate. All of these parameters were dimensionless. Furthermore, A fitting equation was newly proposed for mixing time as a function of four influencing factors. As a result, It was showed that the arrangement of tuyeres has a great effect on mixing time in the ladle and a placement of single tuyere at 2/3R away from the bottom center gave the shortest mixing time.
E-55: Effect of Temperature, Concentration and Particle Size of the Solid Solution of Potassium-ammonium Arsenojarosita Medium NaOH: J. Eliecer Méndez Reyes1; Francisco Patiño Cardona2; Julio Cesar Juárez Tapia1; Mizraim Uriel Flores Guerrero3; Iván A. Reyes Dominguez4; Martín Reyes Pérez1; Aislinn Teja Ruiz1; 1Universidad Autónoma del Estado de Hidalgo; 2Universidad Politécnica Metropolitana de Hidalgo; 3Universidad Tecnológica de Tulancingo; 4Universidad Autónoma de San Luis Potosí
The decomposition experiments corresponding to effect of temperature, concentration and particle size were performed in medium NaOH. The sigmoidal curves (S) show that as increases the temperature or concentration, the induction period decreases. The activation energy value obtained for the progressive conversion period is 65.42 kJ mol-1. For concentrations of OH- <0.005942 mol L-1, the reaction order is 0 and for concentrations of OH- ≥ 0.005942 mol L-1, the reaction order is 1.51, therefore to these conditions, the reaction rate is highly dependent of the concentration of NaOH. The high value of activation energy indicates that the mechanism that controls the decomposition process is the chemical reaction. The high dependence on the reaction medium and high activation energy obtained indicate that to initiate the decomposition reaction a high concentration of OH- and high temperature is required.
E-56: Effects of Zr on the Microstructure and Mechanical Properties of EH36 Shipbuilding Steel: Dapeng Zhao1; Xiaodong Zou1; Cong Wang1; 1Northeastern University, China
Forming fine dispersed inclusions in steel can significantly improve the toughness of the heat affected zone deteriorated by high heat input welding. In prior studies, very few authors have investigated high heat input welding steel with a holistic perspective (from production to application). Therefore, for a better understanding of the production process, this paper tackles the effect of Zr on microstructures and mechanical properties after continuous casting, rolling, and welding. It is found that Zr (34 ppm) can effectively increase the number of inclusions in EH36 slab and plate, refining the microstructure and improving the mechanical properties of steel. However, after the high heat input welding thermal simulation experiment, such content of Zr is not able to inhibit austenite grain growth, or promote the nucleation of intragranular ferrite. It is further suggested that the effects of the contents of O and Zr on the forming of inclusions should be investigated.
E-57: Genetic Influence of Mold Corner Structure on the Strand Corner Temperature in Secondary Cooling Zone during Slab Continuous Casting: Sheng Yu1; Dengfu Chen1; Pei Xu1; Mujun Long1; Kui Lv1; Huamei Duan1; 1Chongqing University
Mold corner structure will control the strand corner temperature by changing fluid flow and heat transfer of molten steel at mold corner. A three-dimensional model coupling fluid flow and heat transfer in the mold and a two-dimensional moving-slice heat transfer model in secondary cooling zone was established to investigate slab corner temperature under different mold corner structure: right-angle, big-chamfer, multi-chamfer and fillet. Results showed that slab corner temperature increased markedly at mold exit through using chamfered mold. Compared with the corner temperature of right-angle slab, corner temperature of big-chamfered, multi-chamfered and fillet slabs were promoted during the straightening process, which would avoid the low ductility temperature zone. When mold corner structure changed from right-angle to big-chamfer, the rise of corner temperature was much higher than that changed from big-chamfer to multi-chamfer or fillet. Furthermore, the corner temperature variation by changing the mold corner structure gradually reduced in secondary cooling zone.
E-58: Growth Kinetics on Boriding Process and Mechanical Behaviour of AISI P20 Steel: Martín Ortiz1; Miguel Flores1; Milton Espinosa2; Oscar Gómez3; Daniel Sánchez1; 1Universidad Autónoma del Estado de Hidalgo; 2Instituto Tecnológico y de Estudios Superiores de Monterrey-ITESM Campus Santa Fe; 3Instituto Tecnológico de Tlanepantla-ITTLA
In this work, the AISI P20 steel was pack-borided in the temperature range of 1123-1223 K for treatments times between 2 and 8 h. A kinetic model was proposed for estimating the boron diffusion coefficients through the Fe2B layers. As a result, the boron activation energy for the AISI P20 steel was estimated as 194.3 kJ mol-1. This value of energy was compared to the literatura data. In addtion, to extend the validity of the present model, two additional boriding conditions were done. The Fe2B layers grown on AISI P20 steel were characterized by use of the following experimental techniques: scanning electron microscopy, X-ray diffraction analysis and the Daimler-Benz Rockwell-C indentation technique. Finally, the scratch and pin-on-disc tests for wear resistance were performed using a LG Motion Ltd and a CSM tribometer respectively under dry sliding conditions.
E-60: Numerical Simulation and Experimental Study on Electromagnetic Field and Heat Flow in Electromagnetic Cold Crucible (EMCC): Hyun-Jae Lee1; Hyun-Do Jung1; Byung-Moon Moon1; 1Korea Institute of Industrial Technology
Electromagnetic cold crucible (EMCC) is one of the most important inductive heating method for melting materials. The magnetic pressure which presents the melts from coming into contact with the inner wall of water-cooled copper crucible suppresses the contamination of reactive metals such as rare earth metals. It is highlighted that the relationship between the parameters related to the configuration of cold crucible, frequency and electric power affects the stabilized non-contact working condition and total energy transfer efficiency. In a joint numerical and experimental study, designing various processing variables and parameters should be investigated to understand physical mechanism and to enhance operation aspect to efficiency of the whole system. In this study, multiphysics consisting of electromagnetic field, heat transfer and fluid dynamics have been solved by a commercial finite element method code.
E-61: Recent Progress of Blast Furnace Cooling Stave in China: Yong Deng1; Jian Liang Zhang1; Ke Xin Jiao1; Bing Ji Yan1; 1University of Science and Technology Beijing
In order to improve the service life of the lining of blast furnace, the application of cast iron cooling stave, cast steel cooling stave and copper cooling stave were summarized in China in recent years. The advantages and disadvantages of cast iron cooling stave, cast steel cooling stave and copper cooling stave were analyzed in detail. The newly developed copper-steel composite cooling stave was introduced. Combined with the actual situation of blast furnace in China, the results show that: the key to ensuring the cooling stave life is to form a stable layer on hot face of the cooling stave.
E-62: Separately Copper Recovery from Iron by Using Solvent Extraction Process: Shun Myung Shin1; Dong Ju Shin1; Sung Ho Joo1; Chang Hyun Oh1; 1Korea Institute of Geoscience & Mineral Resources (KIGAM)
Worldwide demand of copper is consistently increased, so the mineral reserve nation controls over the export of raw ore. Besides, decreasing of grade of copper ore is one of big problems. Hydro-metallurgical process has been developed to treat low grade copper ore. However, it is still difficult to separate copper from iron in process. In this study, we tried to recover copper separately from iron in leaching solution by solvent extraction method. Extraction is carried out by using LIX984N as extractant and artificial leaching solution which contains 18g/L copper and 17g/L iron. At first, pH range that copper separate from iron is verified through pH isotherm experiment. And then, we carried out extraction experiment with dilution rate of leaching solution, pH and the concentration of LIX984N and so on. As a result, copper is extracted 99% from 3 stage counter-current extraction experiment. In this case, iron is extracted only 0.1%.
E-64: Study of a Filter-press Electrochemical Reactor for the Treatment of Industrial Waste: Pedro Ramirez Ortega1; Jose Martinez Vazquez2; Marissa Vargas Ramirez2; 1Universidad Tecnológica de Tulancingo; 2Universidad Autónoma del Estado de Hidalgo
In this work the effect of hydrodynamics and the distribution of potential in the electrolyte on the electrorecuperación of silver in two prototype filter press type electrochemical reactors was analyzed, one model of input-output smooth (RSM) and the other striated (RST). The conditions of simulation in COMSOL Multiphysics® were laminar flow and mass transfer by convection-diffusion. The concentration of silver deposited on the electrode surface after two hours of treatment with current values of -35, -65 and -80 mA, was established based on the cyclic voltammetry and kinetics using electrodeposition tertiary Nernst- Planck. It was concluded that the reactor geometry influenced in the hydrodynamic properties and the concentration of Ag recovered, according to calculation, the velocity profile in the RST was 13.7 times higher with respect to RSM and the recovery of Ag increased a 4% in the RST with respect to RSM to a current value of -80 mA.
E-65: The Effect of Ti Addition and Aging Treat on Microstructure and Mechanical Properties of a Nb-microalloyed Crack Arrest Steel: Dan Chen1; 1Harbin Engineering University
A systematic study on determining the influence of Ti addition on the microstructure and mechanical properties of a Nb-microalloyed crack arrest steel has been carried out. Optical, electron microscopy, X-ray diffraction, transmission electron microscopy, and electron back-scattered diffraction were applied to characterize the microstructure and phase transformation.. The microhardness, Tensile strength and Charpy impact energy were evaluated. Based on these results, the effects of Ti and aging treatment on the microstructure and mechanical properties are discussed. This work was supported by the NSFC Funding (51371062 and U1460102), NSFHLJ (ZD201411), the Project for Innovative Talents of Science and Technology of Harbin (2014RFXXJ006), and the Scientific Research Foundation for the Returned Overseas Chinese Scholars, Heilongjiang Province.
E-66: The Interface Characteristics of High-temperature Melt of CaO-Al2O3-MgO-SiO2 System: Chen Tian1; Qing-hai Pang1; 1University of Science and Technology Liaoning
The interface characteristics between CaO-Al2O3-MgO-SiO2 system and MgO (or Al2O3) at high temperature were studied. The melting point and activity of slag system were calculated by Factsage. Contact and melting process as well as reaction between slag system and MgO (or Al2O3) interface were observed by on-line high temperature equipment. The changes in microstructure of interfacial were observed by metallographic microscope, scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The theoretical analysis about slag system interfacial wetting and reaction behavior was explained by the Gibbs and Guggenheim interface layer model and the Young equation. According to these, wetting behavior or erosion mechanism of different ingredients and basicity of slag system and magnesia(or aluminum) refractory brick can be explored at high temperature.