Mechano-Chemical Synthesis of Biphasic Calcium Phosphates with the Various Ratio of HA and β-TCP

2007 ◽  
Vol 330-332 ◽  
pp. 7-10 ◽  
Author(s):  
Timur R. Tadjiev ◽  
Sung Su Chun ◽  
Suk Young Kim
Keyword(s):  
Milling Time ◽  
Calcium Phosphates ◽  
High Energy ◽  
Planetary Mill ◽  
Phase Identification ◽  
Chemical Processing ◽  
Phosphate Dihydrate ◽  
Xrd Study ◽  
Short Period ◽  
Tcp Phases

Biphasic calcium phosphate powders (BCP) of hydroxyapatite (HA) and tricalcium phosphate (β-TCP) with the various ratio of HA to β-TCP were prepared by utilizing mechanochemical synthesis. Calcium hydrogen-phosphate dihydrate (brushite, CaHPO4⋅2H2O) and calcium carbonate (calcite, CaCO3) powders have been chosen as the starting materials. The original Ca/P ratio of CaHPO4⋅2H2O - CaCO3 batch was set to be 1.67. A mixture of starting materials was milled using a planetary mill (ZrO2 jar and balls) with water for 3, 4, 5, 6 and 7 hrs. The XRD study of calcined powders was conducted for phase identification and for HA/β-TCP ratio as well. The phases of the calcined powders were HA and β-TCP, and the HA/β-TCP ratio varied with the milling time. The mass fraction of HA and β-TCP phases was calculated from the XRD intensities of HA and β-TCP. The ratio of the mixture milled for 4 hrs and calcined at 900°C was 85(HA):15(β-TCP) (BCP 85/15) and the content of β-TCP increased with the milling time. It is believed defective HA powder formed at relatively short period of milling time (less than 3 hrs The research revealed that nanocrystalline BCP powders could be synthesized by an employment of a medium-high energy mechanical activation at room temperatures (~25°C) without any preliminary chemical processing.

scholarly journals Effect of Milling Parameters on the Development of a Nanostructured FCC–TiNb15Mn Alloy via High-Energy Ball Milling

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1225
Author(s):  
Cristina García-Garrido ◽  
Ranier Sepúlveda Sepúlveda Ferrer ◽  
Christopher Salvo ◽  
Lucía García-Domínguez ◽  
Luis Pérez-Pozo ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Ball Mill ◽  
Milling Time ◽  
High Energy ◽  
Planetary Mill ◽  
Nominal Composition ◽  
Mechanically Alloyed ◽  
Milling Parameters ◽  
Energy Ball ◽  
Full Conversion

In this work, a blend of Ti, Nb, and Mn powders, with a nominal composition of 15 wt.% of Mn, and balanced Ti and Nb wt.%, was selected to be mechanically alloyed by the following two alternative high-energy milling devices: a vibratory 8000D mixer/mill® and a PM400 Retsch® planetary ball mill. Two ball-to-powder ratio (BPR) conditions (10:1 and 20:1) were applied, to study the evolution of the synthesized phases under each of the two mechanical alloying conditions. The main findings observed include the following: (1) the sequence conversion evolved from raw elements to a transitory bcc-TiNbMn alloy, and subsequently to an fcc-TiNb15Mn alloy, independent of the milling conditions; (2) the total full conversion to the fcc-TiNb15Mn alloy was only reached by the planetary mill at a minimum of 12 h of milling time, for either of the BPR employed; (3) the planetary mill produced a non-negligible Fe contamination from the milling media, when the highest BPR and milling time were applied; and (4) the final fcc-TiNb15Mn alloy synthesized presents a nanocrystalline nature and a partial degree of amorphization.

Microstructural Transformations of Al2O3-TiO2 and Al2O3-ZrO2 Powders Induced by High-Energy Ball-Milling

2006 ◽  
Vol 45 ◽  
pp. 303-308
Author(s):  
Sandrine Coste ◽  
Ghislaine Bertrand ◽  
Christian Coddet ◽  
Eric Gaffet ◽  
Horst Hahn ◽  
...  
Keyword(s):  
Crystallite Size ◽  
Milling Time ◽  
Tetragonal Zirconia ◽  
Rutile Phase ◽  
High Energy ◽  
Planetary Mill ◽  
Energy Ball ◽  
Yttria Partially Stabilized Zirconia ◽  
Tio2 Phase ◽  
Zro2 System

Superior properties of nanostructured Al2O3 based materials, such as higher hardness and fracture toughness, have been evidenced. In order to optimize their manufacturing, the mechanical activation of the starting powders (Al2O3-TiO2 and Al2O3-ZrO2) was studied. In the present work, Al2O3 powders blended with 13wt% and 44wt% of titania or 20wt% and 80wt% of yttria partially stabilized zirconia have been high-energy ball-milled using a planetary mill, P4 (Fritsch) with steel vials and balls. The effect of the milling time and operating parameters, such as shock energy and friction to total energy ratio, on the powder structural and microstructural evolutions has been determined by SEM, XRD and BET. The transformation of the metastable anatase TiO2 phase into the high pressure TiO2 II phase and rutile phase was evidenced, simultaneously to the decrease of the alumina crystallite size, in the Al2O3-TiO2 system. In the Al2O3-ZrO2 system, the transformation of the monoclinic phase and the decrease of the alumina and tetragonal zirconia crystallite size have been observed.

Nickel Silicides Synthesized by High Energy Ball Milling

2007 ◽  
Vol 353-358 ◽  
pp. 1625-1628 ◽  
Author(s):  
Gen Shun Ji ◽  
Qin Ma ◽  
Tie Ming Guo ◽  
Qi Zhou ◽  
Jian Gang Jia ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Ball Milling ◽  
Milling Time ◽  
High Energy ◽  
Planetary Mill ◽  
High Energy Ball Milling ◽  
X Ray Diffraction ◽  
Microstructure Morphology ◽  
Energy Ball ◽  
Xrd Patterns

The high energy ball milling of Ni-50 atom % Si elemental powder mixtures was carried out using a planetary mill. X-ray diffraction (XRD) was used to identify the phase evolutions during the high energy ball milling period. The microstructure morphology of the powders milled different time was determined by field emission scanning electron microscope (FESEM). The beginning time of mechanical alloying was determined by back scattered electrons (BSE) images. The XRD patterns showed that the nickel peaks intensity and the silicon peaks intensity obviously decreased with milling time increased to 1 hour. BSE images revealed that nickel and silicon powders were not blended uniformly for 1 hour of milling. It was found that NiSi formed as the milling time increased to 5 hours, simultaneously, the nickel peaks and the silicon peaks almost disappeared. That means the obvious mechanical alloying started from 5 hours of milling. BSE images agreed with the result analyzed from XRD patterns. With the milling time further increased from 10 to 75 hours, the NiSi peaks decreased gradually, at the same time, the Ni2Si peaks appeared and then increased gradually.

Study for the Development of Fe-NbC Composites by Advanced PM Techniques

2007 ◽  
Vol 534-536 ◽  
pp. 637-640 ◽  
Author(s):  
Elena Gordo ◽  
B. Gómez ◽  
Roberto González ◽  
E.M. Ruiz-Navas
Keyword(s):  
Carbon Content ◽  
Milling Time ◽  
Sintered Material ◽  
High Energy ◽  
Cold Isostatic Pressing ◽  
Planetary Mill ◽  
Matrix Composites ◽  
Vacuum Sintering ◽  
Composite Powders ◽  
Sintered Materials

The development of Fe-based metal matrix composites (MMCs) with high content of hard phase has been approached by combining the use of advanced powder metallurgy techniques like high-energy milling (HEM), cold isostatic pressing (CIP) and vacuum sintering. The most innovative is the use of HEM for the obtaining of a composite powder avoiding the formation of clusters in the microstructure of the sintered material, and the study of hardenability of sintered materials. A 30 % vol. of NbC particles was mixed with Fe powder by HEM in a planetary mill under Ar atmosphere to prevent oxidation. The optimal milling time was determined by sampling every two hours until 10 hours of milling, characterising the powder by the observation of morphology and microstructure by scanning electron microscopy (SEM), and controlling the carbon content by a LECO analyser. Composite powders were compacted by CIP and then sintered in vacuum at temperatures between 1300 °C and 1375 °C, during 30 min and 60 min. The variation of density, hardness and carbon content with sintering temperature and time, besides the microstructural changes observed, permits to find the optimal conditions of processing. Afterwards, a heat treatment study was performed to study the hardenability of the cermet.

Effect of High Energy Milling on the Magnetic Properties of the WC-10wt.%Co Cemented Carbides

2006 ◽  
Vol 530-531 ◽  
pp. 322-327 ◽  
Author(s):  
J.B. Manuel ◽  
J.H. de Araújo ◽  
Franciné Alves Costa ◽  
Harim Revoredo de Macedo ◽  
Uilame Umbelino Gomes ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Milling Time ◽  
Magnetic Hysteresis ◽  
High Energy ◽  
Planetary Mill ◽  
Liquid Phase Sintering ◽  
Tungsten Carbides ◽  
Powder Mixtures ◽  
X Ray ◽  
High Energy Milling

Cemented tungsten carbides were produced by liquid-phase sintering. In these work high energy milling (HEM) was used to produce homogeneous and finely grained powder mixtures. The milling effect on the magnetic properties of sintered samples is studied. Different mixtures in same composition (WC-10wt.%Co) were prepared by conventional mixture technique and wet HEM up to 300 hs in Planetary Mill. Magnetic hysteresis measurements on the sintered samples detected a significant increase in the coercitive field and a decrease on the saturation magnetization with milling time increasing. X-ray diffractogram show phase transformations with milling time. The Magnetic properties are correlated with phase relations and microstructural properties of the sintered samples.

High-Energy Synthesis of Al-Ti Composite Powders and its Thermal Stability

2014 ◽  
Vol 988 ◽  
pp. 56-61
Author(s):  
Wen Da Zhang ◽  
Jing Yang ◽  
Zhen Min Du ◽  
Bao Wu Pan ◽  
Hong Xu ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Milling Time ◽  
Rotation Speed ◽  
High Energy ◽  
Planetary Mill ◽  
Composite Powders ◽  
Low Intensity ◽  
Heat Treated ◽  
Energy Synthesis ◽  
Diffraction Peaks

The effect of the high-energy synthesis of Al-Ti composite powders in a planetary mill on the as milled and heat treated structures was investigated with XRD and SEM. The results indicate that with the increase of milling time, the intensities of diffraction peaks corresponding to Al and Ti decrease and broaden gradually and the amount of low intensity lines decreases continuously. There is no new intermetallic compound in the Al-Ti mixed powders even after milling 200 h. The increase of rotation speed has significant influences on the Al-Ti composite powders, and milling 50h with rotation speed of 400 rpm has a same effectiveness with milling 200 h with rotation speed of 300 rpm. The diffraction peaks of Al and Ti both disappear in the Al-Ti composite powders milling 50h with a rotation speed of 300 rpm after thermally insulated at 610°C for 2h, indicating the formation of Al3Ti tetragonal phases. The higher the milling energy, the lower the reaction temperature of Al3Ti formation is.

Novel Bioceramic Production via Mechanochemical Conversion from Plate Limpet (Tectura scutum) - Shells

2016 ◽  
Vol 696 ◽  
pp. 45-50 ◽  
Author(s):  
Ahmet Talat Inan ◽  
Oguzhan Gunduz ◽  
Yesim Muge Sahin ◽  
Nazmi Ekren ◽  
S. Salman ◽  
...  
Keyword(s):  
Calcium Phosphates ◽  
Land Snail ◽  
Chemical Processing ◽  
X Ray Diffraction ◽  
Hot Plate ◽  
Natural Sources ◽  
X Ray ◽  
Tcp Phases ◽  
Mussel Shells ◽  
Dental Applications

Calcium phosphates are very important biomaterials for orthopaedic and dental applications. Hydroxyapatite (HA) is one of the important phases used for grafting. Those are produced from synthetic and natural sources with various methods. Especially nano-bioceramics can be produced through calcitic and aragonitic structures (i.e. mussel shells, sea snail shells, land snail shells and sea urchin shells). The plate limpet shells were used. The plate limpet is a gastropod, a soft-bodied invertebrate (an animal without a backbone) that is protected by a very hard, flattened conical shell. In this study the Plate Limpet (Tectura scutum) shells were obtained from a local gift store in Istanbul. The habitation of these limpets broadens from south Alaska down to California - Mexico. First the exact CaCO3 content was measured with thermal analysis (DTA/TGA). Here in this study agitation was carried out on a hot-plate (i.e. mechano-chemical processing). First the temperature was set at 80 °C for 15 min. Then equivalent amount to CaO H3PO4 was added dropwise for HA phase formation and the reaction was set on a hotplate for 8 hours. The dried sediments HA part was divided into 2 groups. One group was sintered to 835 °C and second group to 855 °C. Here x-ray diffraction and scanning electron microscope (SEM) studies were performed. From the study various HA phases and TCP phases were obtained. A previous study done with Atlantic Deer Cowrie encourages nanobioceramic production from natural sources. This study proposes that mechanochemical agitation with very simple way for producing nano-sized calcium phosphates for future bioengineering scaffold applications.

Development of Biodegradable Mg-Ti Alloy Synthesized Using Mechanical Alloying

2016 ◽  
Vol 1133 ◽  
pp. 75-79 ◽  
Author(s):  
Emee Marina Salleh ◽  
Sivakumar Ramakrishnan ◽  
Zuhailawati Hussain
Keyword(s):  
Mechanical Alloying ◽  
Milling Time ◽  
Milled Powder ◽  
Milling Process ◽  
Planetary Mill ◽  
Ti Alloy ◽  
X Ray Diffraction ◽  
Argon Flow ◽  
Diffraction Patterns ◽  
Ti Powder

The aim of this work was to study the effect of milling time on binary magnesium-titanium (Mg-Ti) alloy synthesized by mechanical alloying. A powder mixture of Mg and Ti with the composition of Mg-15wt%Ti was milled in a planetary mill under argon atmosphere using a stainless steel container and balls. Milling process was carried out at 400 rpm for various milling time of 2, 5, 10, 15 and 30 hours. 3% n-heptane solution was added prior to milling process to avoid excessive cold welding of the powder. Then, as-milled powder was compacted under 400 MPa and sintered in a tube furnace at 500 °C in argon flow. The refinement analysis of the x-ray diffraction patterns shows the presence of Mg-Ti solid solution when Mg-Ti powder was mechanically milled for 15 hours and further. Enhancements of Mg-Ti phase formation with a reduction in Mg crystallite size were observed with the increase in milling time. A prolonged milling time has increased the density and hardness of the sintered Mg-Ti alloy.

scholarly journals Mechanochemical Preparation of Slow Release Fertilizer Based on Glauconite–Urea Complexes

Minerals ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 507 ◽  
Author(s):  
Maxim Rudmin ◽  
Elshan Abdullayev ◽  
Alexey Ruban ◽  
Ales Buyakov ◽  
Bulat Soktoev
Keyword(s):  
Milling Time ◽  
Slow Release ◽  
Mechanochemical Activation ◽  
Structural Characteristics ◽  
Fluorescence Analysis ◽  
Planetary Mill ◽  
X Ray Diffraction ◽  
Mechanochemical Method ◽  
X Ray ◽  
Slow Release Fertilizers

We investigated the mechanochemical synthesis of complex slow release fertilizers (SRF) derived from glauconite. We studied the effectiveness of the mechanical intercalation of urea into glauconite using planetary and ring mills. The potassium-nitric complex SRFs were synthesized via a mechanochemical method mixing glauconite with urea in a 3:1 ratio. The obtained composites were analyzed using X-ray diffraction analysis, scanning electron microscopy, X-ray fluorescence analysis, and infrared spectroscopy. The results show that as duration of mechanochemical activation increases, the mineralogical, chemical, and structural characteristics of composites change. Essential modifications associated with a decrease in absorbed urea and the formation of microcrystallites were observed when the planetary milling time increased from 5 to 10 min and the ring milling from 15 to 30 min. Complete intercalation of urea into glauconite was achieved by 20 min grinding in a planetary mill or 60 min in a ring mill. Urea intercalation in glauconite occurs much faster when using a planetary mill compared to a ring mill.

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