Enhancing the Bonding Strength of Plasma-Sprayed HA Coating on Pure Ti

2007 ◽  
Vol 561-565 ◽  
pp. 1553-1556 ◽  
Author(s):  
Sen Yang ◽  
Hau Chung Man
Keyword(s):  
Calcium Phosphate ◽  
Calcium Oxide ◽  
Tricalcium Phosphate ◽  
X Ray Diffraction ◽  
Tetracalcium Phosphate ◽  
X Ray ◽  
Gas Nitriding ◽  
Ha Coating ◽  
Scaffold Structure ◽  
Plasma Sprayed

A layer of bioceramic HA was coated on laser gas nitrided and grit-blasted pure Ti substrates using plasma-spraying technique, respectively. X-ray diffraction analysis showed that the microstructures of the coating were mainly composed of HA, amorphous calcium phosphate and some minute phases of tricalcium phosphate, tetracalcium phosphate and calcium oxide. The experimental results showed that the 3-D TiN dendritic scaffold structure produced on the surface of pure Ti using laser gas nitriding technique in advance could anchor the HA coating and improved the interfacial adherence significantly as compared with those on the grit blasted surfaces.

Synthesis of Alpha-Tricalcium Phosphate by Wet Reaction and Evaluation of Mechanical Properties

2012 ◽  
Vol 727-728 ◽  
pp. 1164-1169 ◽  
Author(s):  
Mônica Beatriz Thürmer ◽  
Rafaela Silveira Vieira ◽  
Juliana Machado Fernandes ◽  
Wilbur Trajano Guerin Coelho ◽  
Luis Alberto Santos
Keyword(s):  
Mechanical Properties ◽  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Calcium Nitrate ◽  
Chemical Precipitation ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Calcium Phosphate Cements

Calcium phosphate cements have bioactivity and osteoconductivity and can be molded and replace portions of bone tissue. The aim of this work was to study the obtainment of α-tricalcium phosphate, the main phase of calcium phosphate cement, by wet reaction from calcium nitrate and phosphoric acid. There are no reports about α-tricalcium phosphate obtained by this method. Two routes of chemical precipitation were evaluated and the use of two calcinations temperatures to obtain the phase of cement. The influence of calcination temperature on the mechanical properties of cement was evaluated. Cement samples were characterized by particle size analysis, X-ray diffraction, mechanical strength and scanning electron microscopy. The results demonstrate the strong influence of synthesis route on the crystalline phases of cement and the influence of concentration of reactants on the product of the reaction, as well as, on the mechanical properties of cement.

Effects of Spraying Parameters on Phase Formation and Distribution in Plasma-Sprayed Hydroxyapatite Coatings

2000 ◽  
Author(s):  
L. Sun ◽  
C.C. Berndt ◽  
R.S. Lima ◽  
A. Kucuk ◽  
K.A. Khor
Keyword(s):  
Opposite Effect ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
Tetracalcium Phosphate ◽  
X Ray ◽  
Impurity Phases ◽  
Hydroxyapatite Coatings ◽  
Spraying Parameters ◽  
Plasma Sprayed ◽  
Spray Dried

Abstract Calcined spray-dried hydroxyapatite (Ca10(PO4)(OH)6; i.e., HA) powders were atmospherically plasma sprayed (APS) using various process parameters. The resulting phases within the coating surface and the interface between the coating and the substrate were analyzed using X-ray diffraction (XRD) methods. This XRD revealed the presence of both amorphous (i.e., amorphous calcium phosphate: ACP) and crystalline phases. The crystalline phases included both HA and some impurity phases from the decomposition of HA, such as tricalcium phosphate (α-TCP and β-TCP), tetracalcium phosphate (TTCP) and calcium oxide (CaO). The crystallinity of HA decreased with increasing spray power and stand-off distance (SOD). The percentage of all impurity phases increased with the spray power. The percentage of both TCP and TTCP decreased with the SOD while the CaO percentage increased. In addition, the percentage of ACP and CaO were higher in the interface than at the surface of the coating while the percentage of TCP and TTCP exhibited the opposite effect.

Synthesis of Chicken’s Eggshells-Based β-Tricalcium Phosphate Bioceramics

2015 ◽  
Vol 1112 ◽  
pp. 458-461
Author(s):  
Kiagus Dahlan ◽  
Nur Aisyah Nuzulia
Keyword(s):  
Fourier Transform ◽  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Sintering Temperature ◽  
X Ray Diffraction ◽  
Diffraction Profile ◽  
X Ray ◽  
Dental Application ◽  
Good Biocompatibility ◽  
Ca:P Ratio

The use of bioceramics for orthopedic and dental application nowadays increases due to their good biocompatibility and osteoconductivity. β-tricalcium phosphate (β-TCP) bioceramics which have excellent biodegradation properties have been in use quite extensively. This paper reports the synthesis of β-TCP bioceramics from precipitation of calcined chicken’s eggshells and phosphoric acid (H3PO4). Chicken’s eggshells were calcined at 1000°C for 5 hours to form calcium oxide (CaO). Various molarities of CaO and H3PO4, between 0.4 M and 2.4 M, were used in this experiment with the Ca:P ratio was kept 1.5:1. After precipitation, the samples were filtered and heated at a sintering temperature of 1000°C for 7 hours. The X Ray Diffraction profile showed that the patterns were affected by the molarity. The patterns of 1.2 M CaO/0.8 M H3PO4 samples showed pure β-TCP, while those of 0.6 M CaO/0.4 M H3PO4 and 2.4 M CaO/1.6 M H3PO4 samples showed the presence of hydroxyapatite and octa calcium phosphate. These findings were also supported by Fourier transform infrared spectra. The purity of the samples shown by the atomic absorption spectroscopy resulted in Ca:P ratio of 1.48:1 which is very closed to that of standard β-TCP bioceramics.

X-ray diffraction studies on plasma-sprayed calcium phosphate-coated implants

1990 ◽  
Vol 24 (6) ◽  
pp. 655-667 ◽  
Author(s):  
B. Koch ◽  
J. G. C. Wolke ◽  
K. de Groot
Keyword(s):  
Calcium Phosphate ◽  
X Ray Diffraction ◽  
X Ray ◽  
Plasma Sprayed

Injectability of a Macroporous Calcium Phosphate Cement

2005 ◽  
Vol 284-286 ◽  
pp. 157-160 ◽  
Author(s):  
J.A. Delgado ◽  
I. Harr ◽  
Amisel Almirall ◽  
Sergio del Valle ◽  
Josep A. Planell ◽  
...  
Keyword(s):  
Particle Size ◽  
Calcium Phosphate ◽  
Calcium Phosphate Cement ◽  
Tricalcium Phosphate ◽  
Extrusion Process ◽  
X Ray Diffraction ◽  
Foaming Agent ◽  
X Ray ◽  
Ir Analysis ◽  
Hydrolysis Of

In this work an injectable and self setting calcium phosphate/albumen foam is developed. The effect of both the amount of albumen and the particle size of the starting a-tricalcium phosphate (a-TCP) powder on the injectability of the cement paste is studied. X-ray diffraction (XRD) and infrared (IR) analysis of the samples reveal that the hydrolysis of a-TCP to calcium deficient hydroxyapatite (CDHA) is not affected by the addition of albumen. A foamed structure formed by spherical pores with diameters between 100 and 500 µm is observed by SEM. This porous structure is maintained after injection of the paste, although some deformation of the pores is produced due to the extrusion process. The injectability of the cements is increased by the presence of albumen as compared with cements prepared in the same conditions but without foaming agent.

Research on Residual Stress and Surfacial Morphology of Bio-Functionally Gradient HA-ZrO2–Ti Coatings

2007 ◽  
Vol 330-332 ◽  
pp. 1301-1304 ◽  
Author(s):  
Cheng Yun Ning ◽  
Ying Jun Wang ◽  
Xiao Feng Chen ◽  
Jian Dong Ye ◽  
Gang Wu ◽  
...  
Keyword(s):  
Residual Stress ◽  
X Ray Diffraction ◽  
X Ray ◽  
Functionally Gradient ◽  
Ha Coating ◽  
Sprayed Coating ◽  
Plasma Sprayed ◽  
Plasma Spraying Process ◽  
Spraying Process ◽  
Scanning Electron

In the present study, Functionally gradient HA-ZrO2-Ti coatings (FGC) on Ti6Al4V were prepared by the plasma spraying process. The residual stress and surfacial morphology of coating were studied by X-ray diffraction and scanning electron microscopy with an energy dispersive spectroscopy. The results showed that: (1) the residual stress of FGC is 72.1Mpa, much lower than that of single HA coating, (2) The surfacial morphology of the FGC showed typical characteristics of plasma-sprayed coating, no microcracks was observed because of its the thermal expansion matched between the gradient coating and substrate.

The Preparation and Morphology of Biphasic Calcium Phosphate Ceramics

2012 ◽  
Vol 506 ◽  
pp. 198-201
Author(s):  
P. Saiwanich ◽  
Kamonpan Pengpat ◽  
G. Rujijanagul ◽  
U. Intatha ◽  
Sukum Eitssayeam
Keyword(s):  
Calcium Phosphate ◽  
Tricalcium Phosphate ◽  
Biphasic Calcium Phosphate ◽  
X Ray Diffraction ◽  
Casting Method ◽  
X Ray ◽  
Gel Casting ◽  
Beta Tricalcium Phosphate ◽  
Ceramic Microstructure ◽  
Ball Milling Technique

In this work, thepreparation and morphology of biphasic calcium phosphate (BCP) have been studied. The biphasic calcium phosphate (BCP) ceramics were prepared by mixing between hydroxyapatite (HA) and Beta-tricalcium phosphate (β-TCP) powderby ball milling technique with different ratios (100:0,80:20,60:40,50:50,40:60, 20:80 and 0:100). After that the mixtures were forming by Gel casting method and then sintered at 1200°C, respectively. The phase formation of the biphasic calcium phosphateceramics were studied by X-ray diffraction (XRD) and their ceramic microstructure,shrinkage and density were investigated.

scholarly journals Microwave-Assisted Fabrication of Mesoporous Silica-Calcium Phosphate Composites for Dental Application

Polymers ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 53
Author(s):  
Adrian Szewczyk ◽  
Adrianna Skwira ◽  
Marta Ginter ◽  
Donata Tajer ◽  
Magdalena Prokopowicz
Keyword(s):  
Calcium Phosphate ◽  
Mesoporous Silica ◽  
Octacalcium Phosphate ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
Coating Solution ◽  
X Ray ◽  
Microwave Assisted ◽  
Calcium Orthophosphates ◽  
Different Types

Herein, the microwave-assisted wet precipitation method was used to obtain materials consisting of mesoporous silica (SBA-15) and calcium orthophosphates (CaP). Composites were prepared through immersion of mesoporous silica in different calcification coating solutions and then exposed to microwave radiation. The composites were characterized in terms of molecular structure, crystallinity, morphology, chemical composition, and mineralization potential by Fourier-transform infrared spectroscopy (FTIR), powder X-ray diffraction (XRD), and scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy (SEM-EDX). The application of microwave irradiation resulted in the formation of different types of calcium orthophosphates such as calcium deficient hydroxyapatite (CDHA), octacalcium phosphate (OCP), and amorphous calcium phosphate (ACP) on the SBA-15 surface, depending on the type of coating solution. The composites for which the progressive formation of hydroxyapatite during incubation in simulated body fluid was observed were further used in the production of final pharmaceutical forms: membranes, granules, and pellets. All of the obtained pharmaceutical forms preserved mineralization properties.

The Relative Merits of Oxides of Hafnium, Cerium and Thorium as Surrogates for Plutonium Oxide in Calcium Phosphate Ceramics

2009 ◽  
Vol 1193 ◽  
Author(s):  
B. L. Metcalfe ◽  
S. K. Fong ◽  
L. A. Gerrard ◽  
I. W. Donald ◽  
E. S. Welch ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Calcination Temperature ◽  
Cerium Oxide ◽  
Absorption Spectroscopy ◽  
Hafnium Oxide ◽  
Intermediate Level ◽  
X Ray Diffraction ◽  
X Ray ◽  
X Ray Absorption ◽  
Additional Phase

AbstractThe choice of surrogate for plutonium oxide for use during the initial stages of research into the immobilization of intermediate level pyrochemical wastes containing plutonium andamericium oxides in a calcium phosphate host has been investigated by powder X-ray diffraction and X-ray absorption spectroscopy. Two non-radioactive surrogates, hafnium oxide and cerium oxide, together with radioactive thorium oxide were compared. Similarities in behaviour were observed for all three surrogates when calcined at the lowest temperature, 750°C but differences became more pronounced as the calcination temperature was increased to 950°C. Although some reaction occurred between all the surrogates and the host to form a substituted whitlockite phase, increasing the temperature led to a significant increase in the cerium reaction and the formation of an additional phase, monazite. Additionally it was observed that the cerium became increasingly trivalent at higher temperatures.

Fabrication and evaluation of calcium phosphate cement scaffold with controlled internal channel architecture and complex shape

2007 ◽  
Vol 221 (8) ◽  
pp. 951-958 ◽  
Author(s):  
X Li ◽  
D Li ◽  
B Lu ◽  
L Wang ◽  
Z Wang
Keyword(s):  
Tissue Engineering ◽  
Calcium Phosphate ◽  
Calcium Phosphate Cement ◽  
Complex Shape ◽  
X Ray Diffraction ◽  
X Ray ◽  
Precise Control ◽  
Internal Channel ◽  
Channel Architecture

The ability to have precise control over internal channel architecture, porosity, and external shape is essential for tissue engineering. The feasibility of using indirect stereo-lithography (SL) to produce scaffolds from calcium phosphate cement materials for bone tissue engineering has been investigated. The internal channel architecture of the scaffolds was created by removal of the negative resin moulds made with SL. Scanning electron microscopy (SEM) showed highly open, well-interconnected channel architecture. The X-ray diffraction examination revealed that the hydroxyapatite phase formed at room temperature in the cement was basically stable up to 850 °C. There was no phase decomposition of hydroxyapatite, although the crystallinity and grain size were different. The ability of resulting structure to support osteoblastic cells culture was tested in vitro. Cells were evenly distributed on exterior surfaces and grew into the internal channels of scaffolds. To exploit the ability of this technique, anatomically shaped femoral supracondylar scaffolds with 300-800 μm interconnected channels were produced and characterized.

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