scholarly journals Sol-derived Hydroxyapatite Ddip-coating of a Porous Ti6Al4V Powder Compact

2016 ◽  
Vol 11 (2) ◽  
pp. 12
Author(s):  
Mustafa Altındiş ◽  
Mustafa Güden ◽  
Chaoying Ni

<p>A sintered porous Ti<sub>6</sub>Al<sub>4</sub>V powder compact with a mean pore size of 63 μm and an average porosity of 37±1% was dip-coated at soaking times varying between 1- and 5-minute using a sol-derived calcium Hydrooxyapatite (HA) powder. The coated compacts were heat-treated at 840 <sup>o</sup>C. The coating thickness was found to increase with increasing soaking time, from 1.87 μm at 1-minute soaking to 9 μm at 5-minute soaking on the average. It was shown that at increasing soaking times, the originally open pores started to close, while at low soaking times the Ti<sub>6</sub>Al<sub>4</sub>V particles were partially coated. The coating layer was shown to be nanoporous and the depth of coating was observed to be relatively shallow: only few particles near the compact surface were HA-coated.</p>

2007 ◽  
Vol 124-126 ◽  
pp. 1789-1792 ◽  
Author(s):  
W.H. Lee ◽  
Y.H. Kim ◽  
N.H. Oh ◽  
Y.W. Cheon ◽  
Y.J. Cho ◽  
...  

Coatings of hydroxyapatite (HA) on the porous-surfaced Ti compact have been conducted by electrostatic spray deposition (EDS). The precursor solution for the HA coating by ESD was prepared by mixing nano-scaled HA powder with ethyl alcohol. As-deposited HA films on the substrate were heat-treated (400 ~ 900 °C) and their physical characteristics were investigated by Scanning Electronic Microscopy (SEM), X-ray Diffractometer (XRD), and X-ray Photoelectronic Spectroscopy (XPS). As-deposited HA films were consisted of HA particles which were uniformly distributed on the Ti substrate, showing a porous structure. By heat treatment, HA particles were agglomerated each other and melted to form a highly dense and homogeneous coating layer consisted of equiaxed nano-scaled grains. HA coatings on the porous-surfaced Ti compact consisted of highly crystalline apatite phase with the Ca/P ratio of about 1.67 were successfully obtained by using ESD.


Author(s):  
N.Z. Hafizah ◽  
J. M. Juoi ◽  
M.R. Zulkifli ◽  
M.A. Musa

The synthesis of Ag-TiO2 coating using AgNO3 precursor is expected to give the properties as pure as Ag nanoparticles. Commonly, high concentration of Ag attributed to agglomeration of silver species and reduction to Ag0 particles on TiO2 surface. In contrast, at lower concentration, Ag species exist as AgO, Ag2O and Ag0. Hence, the exact amount of Ag, which can effectively control the particle growth and agglomeration, surface area, thermal stability and band gap of the TiO2 coating, are still vague and stated differently. In the present study, the effect of Ag content on the phase transformation and surface morphology of Ag-TiO2 coating were reported. TiO2 sol were prepared by incorporating Ag at 2.5, 5 and 7.5 mol % and deposited on unglazed ceramic tiles thru five times dip coating. The deposited Ag-TiO2 coatings were heat treated at 500 °C for 1 hour soaking time. XRD analyses revealed that the deposited Ag-TiO2 coating consists of anatase, rutile, Ag2O and metallic Ag. Almost all the coating surfaces illustrated cracks. Increased Ag content lead to presence of tiny particles on the surfaces and EDX spectrum revealed the presence of Ti, O and metallic Ag particles. However, at the addition of 5 mol % Ag, there was no metallic Ag presence and a dense coating with the lowest thickness of ±11.4µm is observed.


2015 ◽  
Vol 638 ◽  
pp. 67-72
Author(s):  
Ana Maria Salantiu ◽  
Florin Popa ◽  
Petru Pascuta ◽  
Olga Soritau ◽  
Noemi Dirzu ◽  
...  

This work aims to investigate the influence of surface conditioning of porous Ti for enhancing its biological activity, as assessed by in vitro stem cell testing. Porous Ti samples with an average porosity of 32% were processed by Powder Metallurgy with dextrin as a space holder. The samples were subjected to H2O2 treatment to form an enhanced TiO2 film, followed by a heat treatment at 400°C and 600°C aiming to the crystallization of the as-formed amorphous titanium oxide. Samples characterization was performed by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FT-IR) and X-Ray Diffraction (XRD). The treated surfaces revealed to be made of both anatase and rutile TiO2, with groove–shaped structure and cracks on the surface of the TiO2 film. The intrinsic biocompatibility of the chemically modified porous Ti surfaces was assessed in vitro. In our cell culture tests, stem cells were found to attach and proliferate better on the chemically treated Ti surfaces compared to the control untreated Ti surfaces.


Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1298
Author(s):  
Jong Won Kim ◽  
Seon Ju Lee ◽  
Moon Young Choi ◽  
Jin-Hae Chang

4,4′-(4,4′-isopropylidenediphenoxy)bis(phthalic anhydride) (BPADA) as a dianhydride and bis(3-aminophenyl) sulfone (APS) and bis(3-amino-4-hydroxyphenyl) sulfone (APS-OH) as diamines were used to synthesize two types of poly(amic acid) (PAA). Varying amounts (0–5.0 wt%) of water-soluble poly(vinyl alcohol) (PVA) were mixed with PAA, and the resulting blend was heat-treated at different stages to obtain the colorless and transparent polyimide (CPI) blend films. The synthesized blended film completely removed water-soluble PVA in water. The possibility as a porous membrane according to the pore size varied according to the amount of PVA was investigated. The dispersibility and compatibility of CPI containing APS-OH monomer were higher than those of the APS monomer. This could be attributed to the hydrogen-bonding interactions between the CPI main chains and PVA. Scanning electron microscopy was conducted to characterize the material. The results revealed that the pore size of the CPI blend film increased as the PVA concentration increased. It was confirmed that uniform pores of μm-size were observed in CPI. The thermal stabilities, morphologies, optical properties, and solubilities of two CPIs obtained using APS and APS-OH monomers were investigated and their properties were compared with each other.


PLoS ONE ◽  
2014 ◽  
Vol 9 (2) ◽  
pp. e88366 ◽  
Author(s):  
Toshiyuki Kawai ◽  
Mitsuru Takemoto ◽  
Shunsuke Fujibayashi ◽  
Haruhiko Akiyama ◽  
Masashi Tanaka ◽  
...  
Keyword(s):  

2021 ◽  
Vol 410 ◽  
pp. 773-777
Author(s):  
Valentina I. Loganina ◽  
Bassam Shareef Deneef Al Saedi

The article provides information about the stress state protective and decorative coatings during aging. The influence of the discrete nature of the substrate on the change in the stress state of the coatings from the action of the wind load is considered. It was revealed that for each type of coating there is its own critical value of the pore size (unfilled paint), the excess of which leads to cracking of the coatings. A method is proposed for selecting the optimal coating thickness.


2012 ◽  
Vol 487 ◽  
pp. 462-465
Author(s):  
Min Jing Zhan ◽  
Gang Li ◽  
Qiang Wei ◽  
Hua Lei Cui ◽  
Ling Lin

The porous Ti plates with nanograde pore size were successfully prepared by dip-coating technique, using stainless steel plates as support and 400mesh Ti powders as raw material. The stainless steel plates were firstly dipped into Ti slurry and then pulled out with desired withdrawal velocity. After sintered in a vacuum furnace, stainless steel supports were removed by aqua regia. The obtained products were characterized by X-ray diffraction, sanning electron microscope and N2 adsorption–desorption isotherms. The results had shown that the thickness and pore characters of porous Ti plates could be controlled by adjusting the withdrawal velocity. When the withdrawal velocity was controlled between 0.2mm/s and 1mm/s, the porous Ti plates had smooth surface without cracks and the most pores were interconnected. The maximum pore diameters could be less than 300nm and the porosities of porous Ti plates are more than 4.9%. The kind of preparation method has advantages of simple technology, easy operation and high purity. These indicated that the porous sintering Ti plates were promising to be used as ultrafilter membranes.


2011 ◽  
Vol 236-238 ◽  
pp. 1178-1182
Author(s):  
Yan Xin Liu ◽  
Yu Long Wang ◽  
Shen Tao Qin ◽  
Fei Fei Liu

Coating pore structure of low gloss coated paper based on different pigment blends was analyzed using mercury intrusion method in this paper. The results show that pore size of coating layer structure of low gloss coated paper ranges from 20nm-500nm, and the range from 500nm-5000nm is mainly from base paper and interactions between coating color and base paper. Printability of coated paper can be well related with coating pore structure. Print gloss is strongly influenced by pore size and pore volume. Large pore diameters and small pore volume of coating layer structure can improve print gloss. Ink density increases with the increasing of pore diameter while the pore volume is kept constant. The increasing of pore volume of coat layer structure will improve capillary absorption and then improve ink absorption. The control of coating pore structure is very important for producing low gloss coated paper.


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