Structure and morphology of whitlockite coating electrophoretically deposited on NiTi shape memory alloy
Journal Title: Engineering of Biomaterials / Inżynieria Biomateriałów - Year 2017, Vol 20, Issue 140
Abstract
In order to improve the biocompatibility of NiTi shape memory alloy, the surface was modified by formation of multifunctional layer consisted of titanium oxides and whitlockite ceramic. Amorphous TiO2 interlayer was produced on NiTi substrate by autoclaving at 134°C for 30 minutes while the following whitlockite coatings were deposited using electrophoresis (EPD). Electrophoresis was performed under different voltage (from 20 to 80 V) at time periods (from 30 to 120 s). Applied deposition parameters 20 V and 60 s resulted in forming homogenous whitlockite coating, consisted of β-Ca3(PO4)2 and β-Ca2P2O7, on passivated NiTi alloy. In the next step, the material was heat-treated in vacuum condition at 1000°C for 2 h. As a result of sintering crystallization of titanium oxides was observed. The obtained layer was cracks-free. Applied deposition process increased the roughness of surface. Deposited whitlockite agglomerates had an average thickness ca. 5.6 μm. The structure of CaP coating material after applied heat-treatment remained unchanged in comparison to initial powder material. However, the partial decomposition of NiTi parent phase to equilibrium ones was observed. The whitlockite coating was also observed to have no impact on the martensitic transformation responsible for shape memory effect. Additionally, applied sintering condition changed the sequence of martensitic transformation from one to two-step.
Authors and Affiliations
K. Dudek, T. Goryczka
The influence of mineralization conditions on the effectiveness of enzymatic mineralization of hydrogels
Polysaccharide hydrogels are widely used in food industry and medicine. Gellan gum (GG) recently gained a lot of attention as a promising material for tissue regeneration proposes due to its excellent biocompatibility an...
Adhesion of SiO2 layers deposited by means of sol-gel and ALD methods on 316LVM steel
The aim of this study was to evaluate the usefulness of SiO2 layers deposited by two methods - atomic layer deposition (ALD) and sol-gel, on the surface of stainless steel 316LVM used in application of cardiovascular imp...
Investigation of the initial degradation stage and tensile strength of polylactide and its composites with eggshells
The degradation rate of the composite polylactide (PLA) – eggshell powder (ESP), depends on many factors. The main are porosity, particle distribution, the weight load of ESP and chain length, the microstructure of bio-b...
Detonation nanodiamond particles modified by non-steroidal anti-inflammatory drugs in vitro examination
Most recently it has been found that nanodiamond particles have very interesting properties. There are number of research communications that detonation nanodiamond particles (NDPs) are fairly reactive and their surface...
A tubular polycaprolactone/hyaluronic acid scaffolds for nasal cartilage tissue engineering
In this preliminary study, 3D nanofibrous porous scaffolds in the form of spiral tubes for future application as nasal cartilages implants were fabricated by combining polycaprolactone electrospun fibers with drug modifi...