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Pierre Layrolle - One of the best experts on this subject based on the ideXlab platform.

  • influence of ionic strength and carbonate on the ca p Coating Formation from sbf 5 solution
    Biomaterials, 2002
    Co-Authors: F Barrere, C A Van Blitterswijk, K De Groot, Pierre Layrolle
    Abstract:

    Biomimetic calcium-phosphate (Ca-P) Coatings were applied on Ti6Al4V by using simulated body fluids concentrated by a factor 5 (SBF×5). The production of SBF×5 solution was possible by decreasing the pH of the solution to approximately 6 using CO2 gas. The subsequent release of this mildly acidic gas led to a pH rise and thus, increasing supersaturation. After immersion for 5 1/2 h a Ca-P Coating on Ti6Al4V plates and a precipitate simultaneously formed at pH=6.8. Sodium chloride (NaCl) and hydrogencarbonate (HCO3−) contents were studied in relation to CO2 release and Coating Formation by changing their individual concentration in SBF×5 solution. On one hand, NaCl-free or low NaCl-content SBF×5 solution led to the earlier aspecific precipitation in the solution than for SBF×5 solution. In contrast, Ca-P Coating was formed later and was thinner than the Coating obtained in regular SBF×5 solution. High ionic strength delayed precipitation and favored Ca-P heterogeneous nucleation on Ti6Al4V. On the other hand, HCO3− content increased the pH of the solution due to its buffering capacity and influenced the release rate of dissolved CO2. Thus, HCO3− content strongly affected the supersaturation and Ca-P structure. Furthermore, HCO3− favored the attachment of Ca-P mineral on Ti6Al4V by decreasing Ca-P crystal size resulting in a better physical attachment of Ca-P Coating on Ti6Al4V substrate.

  • Influence of ionic strength and carbonate on the Ca-P Coating Formation from SBF×5 solution
    Biomaterials, 2002
    Co-Authors: F Barrere, C A Van Blitterswijk, K De Groot, Pierre Layrolle
    Abstract:

    Biomimetic calcium-phosphate (Ca-P) Coatings were applied on Ti6Al4V by using simulated body fluids concentrated by a factor 5 (SBF×5). The production of SBF×5 solution was possible by decreasing the pH of the solution to approximately 6 using CO2 gas. The subsequent release of this mildly acidic gas led to a pH rise and thus, increasing supersaturation. After immersion for 5 1/2 h a Ca-P Coating on Ti6Al4V plates and a precipitate simultaneously formed at pH=6.8. Sodium chloride (NaCl) and hydrogencarbonate (HCO3−) contents were studied in relation to CO2 release and Coating Formation by changing their individual concentration in SBF×5 solution. On one hand, NaCl-free or low NaCl-content SBF×5 solution led to the earlier aspecific precipitation in the solution than for SBF×5 solution. In contrast, Ca-P Coating was formed later and was thinner than the Coating obtained in regular SBF×5 solution. High ionic strength delayed precipitation and favored Ca-P heterogeneous nucleation on Ti6Al4V. On the other hand, HCO3− content increased the pH of the solution due to its buffering capacity and influenced the release rate of dissolved CO2. Thus, HCO3− content strongly affected the supersaturation and Ca-P structure. Furthermore, HCO3− favored the attachment of Ca-P mineral on Ti6Al4V by decreasing Ca-P crystal size resulting in a better physical attachment of Ca-P Coating on Ti6Al4V substrate.

F Barrere - One of the best experts on this subject based on the ideXlab platform.

  • influence of ionic strength and carbonate on the ca p Coating Formation from sbf 5 solution
    Biomaterials, 2002
    Co-Authors: F Barrere, C A Van Blitterswijk, K De Groot, Pierre Layrolle
    Abstract:

    Biomimetic calcium-phosphate (Ca-P) Coatings were applied on Ti6Al4V by using simulated body fluids concentrated by a factor 5 (SBF×5). The production of SBF×5 solution was possible by decreasing the pH of the solution to approximately 6 using CO2 gas. The subsequent release of this mildly acidic gas led to a pH rise and thus, increasing supersaturation. After immersion for 5 1/2 h a Ca-P Coating on Ti6Al4V plates and a precipitate simultaneously formed at pH=6.8. Sodium chloride (NaCl) and hydrogencarbonate (HCO3−) contents were studied in relation to CO2 release and Coating Formation by changing their individual concentration in SBF×5 solution. On one hand, NaCl-free or low NaCl-content SBF×5 solution led to the earlier aspecific precipitation in the solution than for SBF×5 solution. In contrast, Ca-P Coating was formed later and was thinner than the Coating obtained in regular SBF×5 solution. High ionic strength delayed precipitation and favored Ca-P heterogeneous nucleation on Ti6Al4V. On the other hand, HCO3− content increased the pH of the solution due to its buffering capacity and influenced the release rate of dissolved CO2. Thus, HCO3− content strongly affected the supersaturation and Ca-P structure. Furthermore, HCO3− favored the attachment of Ca-P mineral on Ti6Al4V by decreasing Ca-P crystal size resulting in a better physical attachment of Ca-P Coating on Ti6Al4V substrate.

  • Influence of ionic strength and carbonate on the Ca-P Coating Formation from SBF×5 solution
    Biomaterials, 2002
    Co-Authors: F Barrere, C A Van Blitterswijk, K De Groot, Pierre Layrolle
    Abstract:

    Biomimetic calcium-phosphate (Ca-P) Coatings were applied on Ti6Al4V by using simulated body fluids concentrated by a factor 5 (SBF×5). The production of SBF×5 solution was possible by decreasing the pH of the solution to approximately 6 using CO2 gas. The subsequent release of this mildly acidic gas led to a pH rise and thus, increasing supersaturation. After immersion for 5 1/2 h a Ca-P Coating on Ti6Al4V plates and a precipitate simultaneously formed at pH=6.8. Sodium chloride (NaCl) and hydrogencarbonate (HCO3−) contents were studied in relation to CO2 release and Coating Formation by changing their individual concentration in SBF×5 solution. On one hand, NaCl-free or low NaCl-content SBF×5 solution led to the earlier aspecific precipitation in the solution than for SBF×5 solution. In contrast, Ca-P Coating was formed later and was thinner than the Coating obtained in regular SBF×5 solution. High ionic strength delayed precipitation and favored Ca-P heterogeneous nucleation on Ti6Al4V. On the other hand, HCO3− content increased the pH of the solution due to its buffering capacity and influenced the release rate of dissolved CO2. Thus, HCO3− content strongly affected the supersaturation and Ca-P structure. Furthermore, HCO3− favored the attachment of Ca-P mineral on Ti6Al4V by decreasing Ca-P crystal size resulting in a better physical attachment of Ca-P Coating on Ti6Al4V substrate.

K De Groot - One of the best experts on this subject based on the ideXlab platform.

  • influence of ionic strength and carbonate on the ca p Coating Formation from sbf 5 solution
    Biomaterials, 2002
    Co-Authors: F Barrere, C A Van Blitterswijk, K De Groot, Pierre Layrolle
    Abstract:

    Biomimetic calcium-phosphate (Ca-P) Coatings were applied on Ti6Al4V by using simulated body fluids concentrated by a factor 5 (SBF×5). The production of SBF×5 solution was possible by decreasing the pH of the solution to approximately 6 using CO2 gas. The subsequent release of this mildly acidic gas led to a pH rise and thus, increasing supersaturation. After immersion for 5 1/2 h a Ca-P Coating on Ti6Al4V plates and a precipitate simultaneously formed at pH=6.8. Sodium chloride (NaCl) and hydrogencarbonate (HCO3−) contents were studied in relation to CO2 release and Coating Formation by changing their individual concentration in SBF×5 solution. On one hand, NaCl-free or low NaCl-content SBF×5 solution led to the earlier aspecific precipitation in the solution than for SBF×5 solution. In contrast, Ca-P Coating was formed later and was thinner than the Coating obtained in regular SBF×5 solution. High ionic strength delayed precipitation and favored Ca-P heterogeneous nucleation on Ti6Al4V. On the other hand, HCO3− content increased the pH of the solution due to its buffering capacity and influenced the release rate of dissolved CO2. Thus, HCO3− content strongly affected the supersaturation and Ca-P structure. Furthermore, HCO3− favored the attachment of Ca-P mineral on Ti6Al4V by decreasing Ca-P crystal size resulting in a better physical attachment of Ca-P Coating on Ti6Al4V substrate.

  • Influence of ionic strength and carbonate on the Ca-P Coating Formation from SBF×5 solution
    Biomaterials, 2002
    Co-Authors: F Barrere, C A Van Blitterswijk, K De Groot, Pierre Layrolle
    Abstract:

    Biomimetic calcium-phosphate (Ca-P) Coatings were applied on Ti6Al4V by using simulated body fluids concentrated by a factor 5 (SBF×5). The production of SBF×5 solution was possible by decreasing the pH of the solution to approximately 6 using CO2 gas. The subsequent release of this mildly acidic gas led to a pH rise and thus, increasing supersaturation. After immersion for 5 1/2 h a Ca-P Coating on Ti6Al4V plates and a precipitate simultaneously formed at pH=6.8. Sodium chloride (NaCl) and hydrogencarbonate (HCO3−) contents were studied in relation to CO2 release and Coating Formation by changing their individual concentration in SBF×5 solution. On one hand, NaCl-free or low NaCl-content SBF×5 solution led to the earlier aspecific precipitation in the solution than for SBF×5 solution. In contrast, Ca-P Coating was formed later and was thinner than the Coating obtained in regular SBF×5 solution. High ionic strength delayed precipitation and favored Ca-P heterogeneous nucleation on Ti6Al4V. On the other hand, HCO3− content increased the pH of the solution due to its buffering capacity and influenced the release rate of dissolved CO2. Thus, HCO3− content strongly affected the supersaturation and Ca-P structure. Furthermore, HCO3− favored the attachment of Ca-P mineral on Ti6Al4V by decreasing Ca-P crystal size resulting in a better physical attachment of Ca-P Coating on Ti6Al4V substrate.

C A Van Blitterswijk - One of the best experts on this subject based on the ideXlab platform.

  • influence of ionic strength and carbonate on the ca p Coating Formation from sbf 5 solution
    Biomaterials, 2002
    Co-Authors: F Barrere, C A Van Blitterswijk, K De Groot, Pierre Layrolle
    Abstract:

    Biomimetic calcium-phosphate (Ca-P) Coatings were applied on Ti6Al4V by using simulated body fluids concentrated by a factor 5 (SBF×5). The production of SBF×5 solution was possible by decreasing the pH of the solution to approximately 6 using CO2 gas. The subsequent release of this mildly acidic gas led to a pH rise and thus, increasing supersaturation. After immersion for 5 1/2 h a Ca-P Coating on Ti6Al4V plates and a precipitate simultaneously formed at pH=6.8. Sodium chloride (NaCl) and hydrogencarbonate (HCO3−) contents were studied in relation to CO2 release and Coating Formation by changing their individual concentration in SBF×5 solution. On one hand, NaCl-free or low NaCl-content SBF×5 solution led to the earlier aspecific precipitation in the solution than for SBF×5 solution. In contrast, Ca-P Coating was formed later and was thinner than the Coating obtained in regular SBF×5 solution. High ionic strength delayed precipitation and favored Ca-P heterogeneous nucleation on Ti6Al4V. On the other hand, HCO3− content increased the pH of the solution due to its buffering capacity and influenced the release rate of dissolved CO2. Thus, HCO3− content strongly affected the supersaturation and Ca-P structure. Furthermore, HCO3− favored the attachment of Ca-P mineral on Ti6Al4V by decreasing Ca-P crystal size resulting in a better physical attachment of Ca-P Coating on Ti6Al4V substrate.

  • Influence of ionic strength and carbonate on the Ca-P Coating Formation from SBF×5 solution
    Biomaterials, 2002
    Co-Authors: F Barrere, C A Van Blitterswijk, K De Groot, Pierre Layrolle
    Abstract:

    Biomimetic calcium-phosphate (Ca-P) Coatings were applied on Ti6Al4V by using simulated body fluids concentrated by a factor 5 (SBF×5). The production of SBF×5 solution was possible by decreasing the pH of the solution to approximately 6 using CO2 gas. The subsequent release of this mildly acidic gas led to a pH rise and thus, increasing supersaturation. After immersion for 5 1/2 h a Ca-P Coating on Ti6Al4V plates and a precipitate simultaneously formed at pH=6.8. Sodium chloride (NaCl) and hydrogencarbonate (HCO3−) contents were studied in relation to CO2 release and Coating Formation by changing their individual concentration in SBF×5 solution. On one hand, NaCl-free or low NaCl-content SBF×5 solution led to the earlier aspecific precipitation in the solution than for SBF×5 solution. In contrast, Ca-P Coating was formed later and was thinner than the Coating obtained in regular SBF×5 solution. High ionic strength delayed precipitation and favored Ca-P heterogeneous nucleation on Ti6Al4V. On the other hand, HCO3− content increased the pH of the solution due to its buffering capacity and influenced the release rate of dissolved CO2. Thus, HCO3− content strongly affected the supersaturation and Ca-P structure. Furthermore, HCO3− favored the attachment of Ca-P mineral on Ti6Al4V by decreasing Ca-P crystal size resulting in a better physical attachment of Ca-P Coating on Ti6Al4V substrate.

Daniel Höche - One of the best experts on this subject based on the ideXlab platform.

  • Simulation assisted investigation of substrate geometry impact on PEO Coating Formation
    Surface & Coatings Technology, 2018
    Co-Authors: Xun Ma, Carsten Blawert, Daniel Höche, Karl Ulrich Kainer, Mikhail L. Zheludkevich
    Abstract:

    Abstract Plasma electrolytic oxidation (PEO) technology is widely used for Coating of light metals and their alloys because of the excellent Coating properties it provides and its non-line-of-sight treatment which allows forming Coatings on substrates with complex geometry. However, non-uniform Coating thickness and surface properties may be an issue at different locations on substrates with complex shapes. In order to understand the effect of substrate geometry on PEO Coating Formation and uniformity, AM50 magnesium alloy specimens with drill holes of various diameter to length ratios were coated. PEO Coatings were applied on these substrates in an alkaline electrolyte at constant voltage. Phase composition, Coating morphology, thickness and elements distribution were studied at different locations of the drill holes. Complementary, a 3D model describing the processing is built to simulate and to predict the effect of substrate geometry on the anodic current distribution and Coating Formation using finite element analyses. The model can provide useful inFormation for predicting Coating growth and uniformity towards optimized PEO process design.

  • Investigation of electrode distance impact on PEO Coating Formation assisted by simulation
    Applied Surface Science, 2016
    Co-Authors: Xun Ma, Carsten Blawert, Daniel Höche, Mikhail L. Zheludkevich, Karl Ulrich Kainer
    Abstract:

    Abstract The influence of electrode distance between anode and cathode during plasma electrolytic oxidation (PEO) process on the Coating Formation was investigated by combining experiments and simulation. Firstly a model was built to simulate the effect of electrode distance on the anodic current distribution using finite element analyses. Complementary, PEO Coatings were fabricated on AM50 magnesium alloy in an alkaline electrolyte with different electrode distances applying constant voltage. Phase composition, Coating morphology and thickness were studied for both the front and back sides of the PEO Coating depending on the electrode distance. For paralleled plate-like electrodes, based on Coating uniformity, an optimum electrode distance of 60–80 mm was identified under the chosen experimental conditions. Via correlation of simulation and experimental results, the influence of electrode distance on Coating Formation is explored. It is demonstrated that under constant voltage mode, PEO Coating Formation is affected by electrode distance on both front and back sides of magnesium substrates. This effect is ascribed to the influence of electrode distance on the current distribution in the bath and to the related average current density on the surfaces.

  • Industrial Applications of Laser-Material Interactions for Coating Formation
    Lasers in Materials Science, 2014
    Co-Authors: Peter Schaaf, Daniel Höche
    Abstract:

    Laser Synthesis of TiN Coatings on top of Ti pieces is performed by means of a free electron laser and also conventional lasers in reactive atmospheres. The produced Coatings were investigated by various techniques. The results and properties of the resulting Coatings are presented and discussed in connection with the different laser specialties. For the free electron laser treatment it was found that its ability to tune the pulse timing can be used to tailor the Coating structure and properties (phases, hardness, strain, grain-size, etc.). This is discussed in connection with results of modeling the temperature, the plasma evolution, the mass transport, and the solidification behavior during and after the laser irradiation.

  • role of sintering and clay particle additions on Coating Formation during peo processing of am50 magnesium alloy
    Surface & Coatings Technology, 2012
    Co-Authors: Carsten Blawert, Jun Liang, Yuanding Huang, Daniel Höche
    Abstract:

    Abstract In this study sintering of electrochemical conversion products on the surface of AM50 magnesium alloy by the discharges was identified as an essential step in the Coating Formation in PEO processing. Clay particles were selected as suitable additives because of their relatively low melting point and possible reactions with the substrate–electrolyte conversion products. The comparison of Coatings formed in electrolytes with and without particles clearly indicates a complete change in the microstructure. In the standard electrolytes the Coatings are crystalline while they are amorphous if particles are present though the energy input (process parameters) was more or less the same. Only the presence and incorporation of the particles into the Coating has obviously induced a low temperature reactive liquid phase Formation process, reaching a Coating composition with glass forming ability which is likely due to the fast cooling by the electrolyte. In contrast, the Coating Formation in standard electrolytes has to be considered more like a solid phase sintering. However the results clearly indicate that the sintering of reaction/conversion products by the high energy discharges is a very important step in the Coating Formation and that the sintering by the discharges in PEO processing can be influenced by the use of additives similar to traditional sintering processes.

  • TiN-Coating Formation by pulsed Nd:YAG laser irradiation of titanium in nitrogen
    Journal of Coatings Technology and Research, 2008
    Co-Authors: Daniel Höche, Hendrik Schikora, H. Zutz, Andreas Emmel, Robert Queitsch, Peter Schaaf
    Abstract:

    Titanium was treated by pulsed Nd:YAG laser irradiation in nitrogen atmosphere, which led to nitrogen in-diffusion and TiN Coating Formation. The thickness of the TiN films was about 1.2 μm and the Coatings had a universal hardness of about 11 GPa. The layers were investigated by X-ray diffraction at grazing incidence and resonant nuclear reaction analysis for nitrogen depth profiling. Fitting of the experimental depth profiles gave inFormation about the physical processes (diffusion time and depth) with respect to the achieved hardness. The microscopic properties like lattice constants and the variation of the nitrogen content were evaluated. A relationship between laser scan parameters and Coating properties could be revealed. Thus, it was possible to determine the physical limits such as film thickness, nitrogen content, and hardness of this direct laser synthesis.