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Influence of anodization conditions on deposition of Hydroxyapatite on α/β Ti alloys for osseointegration: Atomic Force Microscopy Analysis

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Transactions of Nonferrous Metals Society of China 2024年

作者： Rania E.Hammam Engie M.Safwat Soha A.Abdel-Gawad Madiha Shoeib Shimaa El-Hadad Faculty of Engineering， Modern University for Technology and Information (MTI) Restorative and Dental Materials Department， National research Centre Giza Chemistry Department， Faculty of Science， Cairo University central metallurgical research and development institute p.o.87

Integrating titanium-based implants with the surrounding bone tissue remains challenging. This study aims to exp.o.e the impact of different anodization voltages （20-80V） on the surface topography of two-phase （α/β） Ti alloys and to p.o.uce Tio2films with enhanced bone formation abilities. Scanning electron microscopy coupled with energy dispersive spectroscopy （SEM-EDS） and atomic force microscopy （AFM） were applied to investigate the morp.o.ogical， chemical， and surface topography of the prepared alloys and to confirm the growth of hydroxyapatite （HA） on their surfaces. Results disclosed that the surface roughness of Tio2films formed on Ti-6Al-7Nb alloys was superior to that of Ti–6Al–4V alloys. Ti-6Al-7Nb alloy anodized at 80 V had the highest yields of HA after immersion in SBF with enhanced HA surface coverage. The developed HA layer had a mean thickness of 128.38 ± 18.13 μm， suggesting its potential use as an orthopedic implantable material due to its p.o.ising bone integration and， hence， remarkable stability inside the human body.

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Technology of Iron Carbide Synthesis

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Journal of Materials Science & Technology 2006年第3期22卷 423-432页

作者： M.Bahgat central metallurgical research and development institute (CMRDI) p.o.box 87-helwan Cairo 11421 Egypt

Iron carbides are very p.o.ising metallurgical p.o.ucts and can be used for steelmaking p.o.ess, where it plays as an alternative raw material with significant economic advantages. Also it has many other applications, e.g. catalysts, magnets, sensors. The present review investigates the different p.o.erties and uses of the iron carbides. The commercial p.o.uction and the different varieties for the iron carbides synthesis （gaseous carburization, mechanochemical synthesis, laser pyrolysis, plasma pyrolysis, chemical vapor deposition and ion implantation） were reviewed. Also the effect of different factors on the carburization p.o.ess like gas composition, raw material, temperature, reaction time, catalyst presence and sulfur addition was indicated.

关键词： Iron carbides Cementite Carburization Reduction

Feasibility of new ladle-treated Hadfield steel for mining purposes

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International Journal of Minerals,Metallurgy and Materials 2018年第3期25卷 300-309页

作者： M.K. El Fawkhry central metallurgical research and development institute (CMRDI) Box 87 Helwan Egypt

A debate has arisen over the possibility of using a new ladle-treated Hadfield steel instead of conventional heat-treated Hadfield steel in mining applications. This debate might be solved by identifying the differences between the mechanical p.o.erties and strain-hardening p.o.erties of conventional heat-treated Hadfield steel and its counterpart ladle-treated Hadfield steel. Tensile and compression tests demonstrated that the ductility of ladle-treated Hadfield steel is similar to that of conventional heat-treated steel. However, the strain-hardening p.o.erty of the ladle-treated Hadfield steel is almost two times higher than that of the heat-treated Hadfield steel. The results of this study demonstrate that the imp.o.ement of the strain-hardening behavior is attributable to the low stacking-fault energy of the main austenite matrix, which results from the high segregation coefficient of carbon and manganese solutes of the main austenite matrix into the new eutectic phase. Superior wear abrasion resistance is a potential consequence of different strain-hardening p.o.erties under low and high loads.

关键词： Hadfield steel ladle treatment p.o.ess wear abrasion resistance strain hardening p.o.erties mechanical p.o.erties

Formation of AlN from Secondary Al Resources

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Journal of Materials Science & Technology 2006年第5期22卷 621-624页

作者： M.Bahgat M.Radwan F.E.Farghaly central metallurgical research and development institute (CMRDI) p.o.box 87 helwan Cairo 11421 Egypt

Synthesis of AlN by NH4Cl-assisted direct nitridation of secondary Al resources was studied. Aluminum alloy scrap contained Mg and Zn element was used. Milled Al scrap （-1 mm） was mixed with NH4Cl and heated at 1000℃ for 1 h in presence of 1 L/min N2 flow gas. The nitrided p.o.uct was evaluated by X-ray diffraction semi-quantitative analysis and scanning electron microscopy （SEM）. Aluminium nitride of 90.5% concentration was obtained with a hexagonal crystalline form. AlN is mostly formed in nano-whisker morp.o.ogy （50～150 nm） which is homogenously distributed.

关键词： AlN Direct nitridation Nanowhisker Secondary resources

Investigation on the mechanical p.o.erties of sintered porous copper compacts

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China particuology 2007年第6期5卷 391-394页

作者： Yasser M.Z. Ahmed Mohamed I. Riad Ahmed I. Zaky Mohammed Abdel-Aziz Mohamed M.H. Shalabi central metallurgical research and development institute CMRDI El-Felzat Street El-Tabbin P.O. Box 87 Helwan Cairo Egypt

In line with recent attention on porous metals having low and medium porosities in the range of 20-50%, this paper studies the effect of porosity on the mechanical p.o.erties of sintered copper compacts. Experiments were designed to investigate the effect of porosity, applied stress and sliding velocity on the wear rate of copper compacts, leading to the finding that the effects of both porosity and applied stress of the wear test on the wear rate are app.o.imately similar and higher than that of sliding velocity. The investigation concerning the effect of porosity on compressive strength indicated that the stress-strain curve of high-porosity compact exhibited identifiable ultimate strength points, though low-porosity compact showed distinct stages of elastic plastic behavior.

关键词： porous copper Wear rate Compressive strength Experimental design technique

Characterization of some Egyptian serpentinites used as ornamental stones

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Chinese Journal of Geochemistry 2008年第2期27卷 140-149页

作者： I.S. Ismael M.S. Hassan Faculty of Education Suez Canal UniversitySuezEgypt Central Metallurgical Research & Development InstituteP.O. Box 87 HelwanCairoEgypt Faculty of Education Suez Canal UniversitySuez Egypt Central Metallurgical Research&Development InstituteP.O. Box 87 HelwanCairoEgypt

Egypt is characterized by wide occurrence of serpentinites, particularly in the central and southern parts of Eastern Desert. There are several cooperate factors that affect the serpentinites used as ornamental stones. These factors involve mineralogical characteristics (including mineral composition and microstructure parameter), physical p.o.erties and mechanical p.o.erties. Antigorite is an essential serpentinite mineral, with a minor amount of chrysotile. Talc, carbonates (magnesite and dolomite) and tremolite are the main associated minerals. Quality and quantity of associated minerals such as talc and carbonates (dolomite and magnesite) affect the p.o.erties of serpentinites used as ornamental stones. Carbonates are resistant to weathering but suffer from acidic cleaning agents in interior use, whereas serpentinites with a high content of talc used on external faces undergo an increase in volume and a consequent rapid degradation. Studied serpentinites are characterized by relatively small grain size with foliated texture, low water absorption, low porosity, and high abrasion resistance. In the samples studied the uniaxial compressive strength (UCS) varies between 89 and 189 Mpa, with an average of 152 Mpa. According to the classification of Bell (1992), sample No. B8 is very high in strength while the rest high in strength.

关键词：蛇纹岩装饰材料水分吸收颗粒尺寸

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 p.o.p.o.ite 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 Mgp.o.-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

Martensitic transformation and magnetic p.o.erties of aged Ni-Fe-Ga-Ti shape memory alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 867-873页

作者： Nader El-Bagoury Mahmoud Mohamed Hessien Magdy Abdel Wahab Kaseem Chemistry Department Faculty of Science TAIF University P.O. Box 888 El-Haweyah El-Taif Saudi Arbia central metallurgical research and development institute (CMRDI) P.O. Box 87 Helwan Cairo Egypt Head of National Authority for Quality of Education Assurance and Accreditation Nasr City Cairo P.O. Box 11461 Egypt

This article reports the effect of ageing on the microstructure, martensitic transformation, magnetic p.o.erties, and mechanical p.o.erties of Ni51FelsGa27Ti4 shape memory alloy. There are five specimens of this alloy aged at 573 up to 973 K for 3 h per each. This range of ageing temperature greatly affects the microstructure of the alloy. As the ageing temperature increased from 573 up to 973 K, the microstructure of Ni51FelsGa27Ti4 alloy gradually changed from the entirely martensitic matrix at 573 K to the fully austenitic microstructure at 973 K. The volume fraction of precipi- tated Ni3Ti particles increased with the ageing temperature increasing from 573 to 773 K. Further increasing the ageing temperature to 973 K decreased the content of Ni3Ti in the microstructure. The martensitic transformation tempera- ture was decreased steadily by increasing the ageing temperature. The magnetization saturation, remnant magnetization, and coercivity increased with the ageing temperature increasing up to 773 K. A further increase in ageing temperature decreased these raagnetic p.o.erties. Moreover, the hardness values were gradually increased at first by increasing the ageing temperature to 773 K, and then dramatically decreased to the lowest value at 973 K.

关键词： magnetic materials shape memory effect ageing microstructure martensitic transformations magnetic p.o.erties hardness

Structural, elastic and electronic p.o.erties for M_2 XC (M=Ti and Cr, X=Ga and Al) phases from ab initio calculations

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Acta Metallurgica Sinica(English Letters) 2011年第4期24卷 255-270页

作者： B. Ghebouli M.A. Ghebouli M. Fatmi N. Bouarissa M. Benkerri I.A. Ibrahim Laboratory of Study of Surfaces and Interfaces of Solids Materials Department of Physics Faculty of Science University of Setif Department of physics University Center research Unit on Emerging Materials Ferhat Abbas University of Setif Department of physics Faculty of Sciences King Khalid University central metallurgical research and development institute p.o. box: 87 helwan 11424 Cairo Egypt

The first-principles study of the structural, elastic and electronic p.o.erties of the M2XC phases depending on the type of M transition metal （M are Ti and Cr） and on X （X are Ga and A1） was reported. The calculations are performed using the pseudo-potential plane-wave app.o.ch in both the local density and generalized gradient app.o.imations. The elastic constants are calculated using the static finite strain technique. Features such as structural and elastic parameters, Debye tem- perature, sound velocities and their pressure dependence have been investigated. In agreement with experimental and previous theoretical findings, it is found that the compressibility along a and c axis depends on the valence electron concentration （VEC）. Correlations revealing the governing role of the X and M elements on the machinability indices of the material have been examined. The electronic p.o.erties have been discussed in terms of chemical bonding showing that bonding is due to Md-Cp and Md-Xp hybridizations. M-C bonds are stiffer than M-X ones and A1-Ti （Cr-C） bonds are stiffer than those corresponding to Ti-C （A1-Cr）. It is shown that the stiffness of the M-X and M-C bonds increases with increasing the number of VEC.

关键词： M2XC phases ab initio pressure effect Band structures