Study on crystallization kinetics of plasma sprayed hydroxyapatite coating

Hydroxyapatite coatings were synthesized on Ti-6Al-4V substrates using the plasma spraying process followed by vacuum and atmospheric post-heat treatments at various elevated temperatures. This study provides an evaluation of the bonding strength and crystallization rate of HACs resulting from the variations in crystallinity and thermal induced cracking. Experimental results provide evidence that the atmospheric heat-treated HACs possessed higher crystallization rate than the vacuum-heated specimens. It implies that the presence of an atmosphere with moisture plays an important role in improving the crystallization of HACs. The bonding strength of all samples was improved with increasing HA crystallization, and the optimal heating condition was found to be about 600 C. However, the crystallization-induced defects result in a serious microstructure and bonding strength degradation when the heating temperatures were higher than 600 C for both post-heat methods. On the basis of the fracture morphologies observation and the bonding strength data fluctuation of both heating conditions, the Weibull distribution function provides a powerful statistical analysis for assessing the failure mechanism and the reliability of plasma-sprayed and post heat-treated HACs.

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“…It is recognized that HA crystallization should follow the second order reaction kinetics of Arrhenius equation, [23][24][25] as below:…”

Section: Crystallization Effect Of Post-heat Treatmentsmentioning

confidence: 99%

Effect of Crystallization on the Bonding Strength and Failures of Plasma-Sprayed Hydroxyapatite

Yang

Lui

2007

Mater. Trans.

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“…Previous studies have indicated that the kinetics of crystallization and chemical reactions during heat treatments are significantly related to heating temperatures, which is recognized as a main factor for promoting HA crystallization [Chang et al, 1999;Campos et al, 2002;Roeder et al, 2006]. Since the IOC value represents the degree of crystallization for heat-treated HACs, it can be recognized of the conversion ratio from ACP to crystalline HA under different heating conditions.…”

Section: Affected Factors On Crystallization During Heat Treatmentsmentioning

confidence: 99%

“…Since the IOC value represents the degree of crystallization for heat-treated HACs, it can be recognized of the conversion ratio from ACP to crystalline HA under different heating conditions. Considering the theory of chemical reaction kinetics and the definition of IOC for crystallized HACs, the HA crystallization process should follow the Arrhenius equation [Chang et al, 1999;Huang et al, 2000;Liu et al, 2001; C.W. as represented in Eq.…”

Section: Affected Factors On Crystallization During Heat Treatmentsmentioning

confidence: 99%

Effect of Hydrothermal Self-Healing and Intermediate Strengthening Layers on Adhesion Reinforcement of Plasma-Sprayed Hydroxyapatite Coatings

Yang¹,

Lui²

2012

Advanced Plasma Spray Applications

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“…Hydroxyapatite Ca 10 (PO 4 ) 6 (OH) 2 (HA) has excellent biocompatibility and bioactivity [10] but cannot be used as a medical implant because of its poor mechanical properties [11]. HA is therefore used as a coating material on metallic implants, such as those made of titanium and its alloys [12].…”

Section: Introductionmentioning

confidence: 99%

Modification of a Ti–Mo alloy surface via plasma electrolytic oxidation in a solution containing calcium and phosphorus

Simka

Krząkała

Korotin

et al. 2013

Electrochimica Acta

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a b s t r a c tInvestigations into the surface modification of a Ti-15Mo alloy via plasma electrolytic oxidation are reported. The oxidation process was conducted in a solution containing Ca(H 2 PO 2 ) 2 , H 3 PO 4 , or (HCOO) 2 Ca. Anodisation was performed at voltages in the range of 100-400 V. The morphology of the sample surface did not change during alloy oxidation at lower voltages. Higher voltages led to the incorporation of calcium and phosphorus or of calcium only into the formed oxide layer and to significant modification of the surface morphology. Based on the SEM and EDX analysis results, a set of samples was selected for further investigations. To study the surface of the Ti-Mo alloy after anodic oxidation, we used scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thin-layer X-ray diffraction (TL-XRD), and X-ray photoelectron spectroscopy (XPS). The electrochemical characteristics of the modified alloy in Ringer's solution were determined. Anodisation results in a considerable increase in the corrosion resistance of the Ti-15Mo alloy.

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Study on crystallization kinetics of plasma sprayed hydroxyapatite coating

Cited by 25 publications

References 16 publications

Effect of Crystallization on the Bonding Strength and Failures of Plasma-Sprayed Hydroxyapatite

Effect of Crystallization on the Bonding Strength and Failures of Plasma-Sprayed Hydroxyapatite

Effect of Hydrothermal Self-Healing and Intermediate Strengthening Layers on Adhesion Reinforcement of Plasma-Sprayed Hydroxyapatite Coatings

Modification of a Ti–Mo alloy surface via plasma electrolytic oxidation in a solution containing calcium and phosphorus

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