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Interpretable modeling of metallurgical responses for an industrial coal column flotation circuit by XGBoost and SHAP-A “conscious-lab” development

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International Journal of Mining Science and Technology 2021年第6期31卷 1135-1144页

作者： S.Chehreh Chelgani H.Nasiri M.Alidokht Minerals and metallurgical Engineering Dept.of CivilEnvironmental and Natural Resources EngineeringLuleåUniversity of TechnologySE-97187 LuleåSweden Department of Computer Engineering Amirkabir University of TechnologyTehranIran Tabas Parvardeh Coal Company(TPCCO) BirjandIran

Surprisingly,no investigation has been explored relationships between operating variables and metallurgical responses of coal column flotation(CF) circuits based on industrial databases for under operation *** a novel approach,this study implemented a conscious-lab "CL" for filling this *** this approach,for developing the CL dedicated to an industrial CF circuit,SHapley Additive explanations(SHAP) and extreme gradient boosting(XGBoost) were powerful unique machine learning systems for the first time *** explainable artificial intelligence models could effectively convert the dataset to a basis that improves human capabilities for better understanding,reasoning,and planning the *** could provide precise multivariable correlation assessments between the CF dataset by using the Tabas Parvadeh coal plant(Kerman,Iran),and showed the importance of solid percentage and washing water on the metallurgical responses of the coal CF *** could predict metallurgical responses(R-square> 0.88) based on operating variables that showed quite higher accuracy than typical modeling methods(Random Forest and support vector regression).

关键词： SHAP XGBoost Explainable AI Coal flotation Separation efficiency

Friction assisted solid state lap seam welding and additive manufacturing method

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Defence Technology（防务技术） 2016年第1期12卷 16-24页

作者： Prasad Rao KALVALA Javed AKRAM Mano MISRA dept. of metallurgical Engineering University of Utah

This paper describes results of seam welding of relatively high temperature melting materials, AISI 304, C-Mn steels, Ni-based alloys, CP Cu, CP Ni, Ti6Al4V and relatively low temperature melting material, AA6061. It describes the seam welding of multi-layered similar and dissimilar metallic sheets. The method described and involved advancing a rotating non-consumable rod(CP Mo or AISI 304) toward the upper sheet of a metallic stack clamped under pressure. As soon as the distal end of the rod touched the top portion of the upper metallic sheet, an axial force was applied. After an initial dwell time, the metallic stack moved horizontally relative to the stationery non-consumable rod by a desired length, thereby forming a metallurgical bond between the metallic sheets. Multi-track and multi-metal seam welds of high temperature metallic sheets, AISI 304, C-Mn steel,Nickel-based alloys, Cp Cu, Ti6Al4V and low temperature metallic sheets, AA6061 were obtained. Optical and scanning electron microscopy examination and 180 degree U-bend test indicated that defect free seam welds could be obtained with this method. Tensile- shear testing showed that the seam welds of AISI 304, C-Mn steel, Nickel-based alloy were stronger than the starting base metal counterparts while AA6061 was weaker due to softening. The metallurgical bonding at the interface between the metallic sheets was attributed to localized stick and slip at the interface, dynamic recrystallization and diffusion. The method developed can be used as a means of welding, cladding and additive manufacturing.

关键词： Lap seam welding Friction assisted welding Solid-state welding Cladding Additive manufacturing

Effect of Nano-sized B4C Addition on the Mechanical Properties of ZA27 Composites

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Journal of Wuhan University of Technology(materials Science) 2017年第4期32卷 747-752页

作者： R.Dalmis H.Cuvalci A.Canakci O.Guler Dokuz Eylul University Faculty of Engineering dept. of metallurgical and materials Engineering Tinaztepe Campus 35397 Buca - Izmir / Turkey Department of metallurgical and materials Engineering Engineering Faculty Karadeniz Technical University Trabzon Turkey Abdullah Kanca Vocational School of Higher Education Karadeniz Technical University Trabzon Turkey

In order to understand the influence of nano-sized B4C additive on ZA27 alloy, mechanical and physical properties of ZA27-B4C nanocomposites were investigated in terms of B4C content. While physical properties were determined in terms of microstructural studies, density and porosity tests, mechanical properties were determined in terms of ultimate tensile strength（UTS） and hardness experiments. Morphological and microstructural studies were carried out with scanning electron microscopy（SEM）. The experimental results indicate that nano-sized B4C can be used to enhance the mechanical properties of ZA27 alloy effectively. The highest mechanical performance can be obtained at ZA27-0.5% B4C（in weight） nanocomposite with values of tensile strength（247 MPa） and hardness（141,18 BH） and low partial porosity（0.5%）. After a pick point, increasing B4C ratio may cause the formation of agglomeration in grain boundaries, that＇s why density, tensile strength, and hardness values are declined.

关键词： metal matrix nanocomposite ZA27 alloy hot pressing powder metallurgy

Microstructural Evolution of NiTi47.7Cu6.3 Alloy during Hot Deformation

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Journal of materials Science & Technology 2011年第10期27卷 951-960页

作者： Amir Etaati Kamran Dehghani Mining and metallurgical Eng.dept. Amirkabir Univ.Tech.

In the present work, the hot workability and microstructural evolution of ***6.3 （at.%） shape memory alloy were investigated by using wedge-rolling test. The wedge specimens were subjected to hot rolling at the temperatures of 700-1000℃. The microstructural evolutions at the strains of 0.05, 0.15, 0.2, 0.25 and 0.3 were then characterized by optical microscopy and scanning electron microscopy （SEM） as well as energy dispersive spectrometry （EDS） technique. Depending on the deformation temperature and strain, the dynamic recrystallization （DRX） could occur, leading to the refining of the microstructure. At low temperatures of 700 and 800℃ there was no sign of DRX at all studied strains. At these temperatures, the formed fine needle-like precipitates pinned the grain boundaries and prevented them from bulging/migration. By contrast, at higher temperatures of 900 and 1000℃, the DRX took place at the critical strains lower than 0.25 and 0.15, respectively. However, at higher temperatures, strain-induced-boundary-migration （SIBM） mechanism resulted in the formation of DRX grains.

关键词： Deformation Wedge rolling test Dynamic recrystallization Ni-rich Nitinol NiTiCu

Polysaccharides-based pyrite depressants for green flotation separation:An overview

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International Journal of Mining Science and Technology 2023年第10期33卷 1229-1241页

作者： A.Asimi Neisiani R.Saneie A.Mohammadzadeh D.G.Wonyen S.Chehreh Chelgani Department of Mining and metallurgical Engineering Yazd UniversityYazd 89195-741Iran Department of materials Engineering The University of British ColumbiaVancouverBC V6T 1Z4Canada Laboratory for Strategic materials Department of Chemical Engineering and Applied ChemistryUniversity of TorontoToronto M5S 3E5Canada Department of Material Science and Engineering(Mining and Mineral Processing Engineering) African University of Science and TechnologyAbuja P.M.B 681Nigeria Minerals and metallurgical Engineering Swedish School of MinesDept.of CivilEnvironmental and Natural Resources EngineeringLuleå University of TechnologyLuleå SE-97187Sweden

Froth flotation is an essential processing technique for upgrading low-grade *** separation would not be efficient without chemical surfactants(collectors,depressants,frothers,etc.).Depressants play a critical role in the selective separation of minerals in that they deactivate unfavorable mineral surfaces and hinder them from floating into the flotation concentration *** is the most common and challenging sulfide gangue,and its conventional depressants could be highly harmful to nature and ***,using available,affordable,eco-friendly polymers to assist or replace hazardous reagents is mandatory for a green ***-based(starch,dextrin,carboxymethyl cellulose,guar gum,etc.)polymers are one of the most used biodegradable depressant groups for pyrite *** the satisfactory flotation results obtained using these eco-friendly depressants,several gaps still need to be addressed,specifically in investigating surface interactions,adsorption mechanisms,and parameters affecting their depression *** a unique approach,this review comprehensively discussed previously conducted studies on pyrite depression with polysaccharide-based ***,practical suggestions have been provided for future assessments and developments of polysaccharide-based depressants,which pave the way to green *** robust review also explored the depression efficiency and various adsorption aspects of naturally derived depressants on the pyrite surface to create a possible universal trend for each biodegradable depressant derivative.

关键词： Green flotation Pyrite depression Eco-friendly depressants Adsorption mechanisms

Rock composition and origin of the Duwi Formation calcareous rocks, Upper Egypt

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Chinese Journal Of Geochemistry 2005年第4期24卷 316-326页

作者： Baioumy H.M. Attia A.M. Boulis S.N. Hassan M.S. Helmy M.E. Central metallurgical Research and Development Institute 87 Helwan Cairo EgyptCentral Metallurgical Research and Development Institute 87 Helwan Cairo EgyptCentral Metallurgical Research and Development Institute 87 Helwan Cairo EgyptCentral Metallurgical Research and Development Institute 87 Helwan Cairo EgyptGeology Dept. Faculty of Science Ain Shams University Abbasia Cairo Egypt

Upper Cretaceous phosphorite beds of the Duwi Formation, Upper Egypt, are intercalated with limestone, sandy limestone, marl, calcareous shales, and calcareous sandstone. Calcareous intercalations were subjected to field and detailed petrographic, mineralogical and geochemical investigations in order to constrain their rock composition and origin.; Mineralogically, dolomite, calcite, quartz, francolite and feldspars are the non-clay minerals. Smectite, kaolinite and illite represent the clay minerals. Major and trace elements can be classified as the detrital and carbonate fractions based on their sources. The detrital fraction includes the elements that are derived from detrital sources, mainly clay minerals and quartz, such as Si, Al, Fe, Ti, K, Ba, V, Ni, Co, Cr, Zn, Cu, Zr, and Mo. The carbonate fraction includes the elements that are derived from carbonates, maily calcite and dolomite, such as Ca, Mg and Sr. ; Dolomite occurs as being dense, uniform, mosaic, very fine-to-fine, non-ferroan, and non-stoichiometrical, suggesting its early diagenetic formation in a near-shore oxidizing shallow marine environment. The close association and positive correlation between dolomite and smectite indicates the role of clay minerals in the formation of dolomite as a source of Mg{2}-rich solutions.; Calcareous rocks were deposited in marine, oxidizing and weakly alkaline conditions, marking a semi-arid climatic period. The calcareous/argillaceous alternations are due to oscillations in clay/carbonate ratio.

关键词：岩石埃及石灰质白云石成岩作用

Characterization and separation of pyrite from Abu Tartur black shale

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International Journal of Mining Science and Technology 2015年第4期25卷 565-571页

作者： Ibrahim S.S. El Kammar A.M. Guda A.M. Central metallurgical R&D Institute CMRDI Geology dept. Faculty of Science National Research Astronomical & Geophysical Institute NRIAG

This work aimed for pyrite separation from Abu Tartur black shale as a source of sulfur to be an added economic value of Abu Tartur area. The considered samples in the present work were collected from a core drilled in Abu Tartur plateau representing the pyrite-rich black shale of the U. Cretaceous age, Sample characterization was carried out using petrographic microscope, XRD, DTA/DTG, C/S and XRF techniques. Clay minerals, silt-sized quartz, calcite, and hematite were the main minerals associating pyr- ite （5.34g）. Liberation behavior of the sample was about 80% below 5 μm. Sample processing was achieved through one-day soaking followed by classification using I inch Mozley hydro-cyclone where about 35.5% by weight went to underflow and 64.5% went to overflow. The underflow product was subjected to an advanced gravity separation process using SB-40 Falcon Concentrator through a CCD statistical design prepared by Design-Expert 6.0 software proposed to opti- mize the separation process through a study for the effects of frequency （Hz） and water pressure （Psi） on both assay and recovery of the sulfur-rich heavy fraction. A heavy concentrate weighed 10.90% with inorganic sulfur content reached 11.37% （21.24% pyrite） with overall recovery （50.01%） was obtained after two cleaning at the optimum conditions.

关键词： Abu Tartur plateau Black shale Pyrite Falcon Concentrator

Effect of metallurgical Behaviour at the Interface between Ceramic and Interlayer on the Si_3N_4/1.25Cr-0.5Mo Steel Joint Strength

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Journal of materials Science & Technology 1998年第1期14卷 20-24页

作者： Huaping XIONG (dept. of materials Science and Engineering, Jilin University of Technology, Changchun 130025, China) dept. of materials Science and Engineering Jilin University of Technology Changchun 130025 China

By using newly developed CuNi5~25Ti16~28 B rapldly solidifled brazing filler the joining of Si3 N4/1.25Cr-0.5Mo steel has been carried out with interlayer method. If employing the interlayer structure of steel (0.2 mm)/W (2.0 mm)/Ni(0.2 mm), the joint strength can be increased greatly compared with employing that of Ni/W/Ni, and the three point bend strength of the Joint shows the value of 261 MPa. The metallurgical behaviour at the interface between Si3N4 and the interlayer has been studied. It is found that Fe participated in the interfacial reactions between Si3N4 and the brazing filler at the Si3N4/steel (0.2 mm) interface and the compound Fe5Si3 was produced. However, since the reactions of Fe with the active Ti are weaker than those of Ni with Ti, the normal inter facial reactions were still assured at the interface of Si3N4/steel (0.2 mm) instead of Si3N4/Ni (0.2 mm), resulting in the improvement of the joint strength. The mechanism of the formation of Fe5Si3 is also discussed. Finally, some ideas to further ameliorate and simplify the interlayer structure are put forward.

关键词： Si Effect of metallurgical Behaviour at the Interface between Ceramic and Interlayer on the Si3N4/1.25Cr-0.5Mo Steel Joint Strength Ni Cr Mo

Thermodynamic Analysis of Ag_3Ge Phase Formation

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Journal of materials Science & Technology 1997年第6期13卷 524-526页

作者： O.P.Pandey(School of Basic and Applied Sciences, Thapar Institute of Engineering and Technology Patiala-147 001, India )S.N.Ojha and S.Lele(dept. of metallurgical Engineering, Banaras Hindu University, Varanasi-221 005, India) School of Basic and Applied Sciences Thapar Institute of Engineering and Technology Patiala-147 001 India dept. of metallurgical Engineering Banaras Hindu University Varanasi-221 005 India

In the present work a thermodynamic model is presented for the nucleation of metastable Ag3Ge phase from the undercooled melt in Ag-Ge alloy system. It is shown that under kinetically induced favourable condition, nucleation of a single phase compound with an approximate stoichiometry Ag3Ge has greater affinity for nucleation over Ag and Ge based phases requiring diffusion in the liquid.

关键词： Ag AIME Ge