Enhanced mechanical properties of porous titanium implants via in-situ synthesized titanium carbide in lamellar pore walls

Object Porous biomaterials with adequate pore structure and appropriate mechanical properties are expected to provide a new generation of devices for spinal interbody fusion because of their potential to eliminate bone grafting. The purpose of this study was to evaluate the fusion characteristics of porous bioactive titanium implants using a canine anterior interbody fusion model. Methods Porous titanium implants sintered with volatile spacer particles (porosity 50%, average pore size 303 μm, compressive strength 116.3 MPa) were subjected to chemical and thermal treatments that give a bioactive microporous titania layer on the titanium surface (BT implant). Ten adult female beagle dogs underwent anterior lumbar interbody fusion at L6–7 using either BT implants or nontreated (NT) implants, followed by posterior spinous process wiring and facet screw fixation. Radiographic evaluations were performed at 1, 2, and 3 months postoperatively using X-ray fluoroscopy. Animals were killed 3 months postoperatively, and fusion status was evaluated by manual palpation and histological examination. Results Interbody fusion was confirmed in all five dogs in the BT group and three of five dogs in the NT group. Histological examination demonstrated a large amount of new bone formation with marrowlike tissue in the BT implants and primarily fibrous tissue formation in the NT implants. Conclusions Bioactive treatment effectively enhanced the fusion ability of the porous titanium implants. These findings, coupled with the appropriate mechanical properties in load-bearing conditions, indicate that these porous bioactive titanium implants represent a new generation of biomaterial for spinal interbody fusion.

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Porous Titanium Surfaces to Control Bacteria Growth: Mechanical Properties and Sulfonated Polyetheretherketone Coatings as Antibiofouling Approaches

Metals ◽

10.3390/met9090995 ◽

2019 ◽

Vol 9 (9) ◽

pp. 995 ◽

Cited By ~ 3

Author(s):

Ana M. Beltrán ◽

Ana Civantos ◽

Cristina Dominguez-Trujillo ◽

Rocío Moriche ◽

José A. Rodríguez-Ortiz ◽

...

Keyword(s):

Mechanical Properties ◽

Mean Free Path ◽

Porous Titanium ◽

Titanium Implants ◽

Equivalent Diameter ◽

Bacterial Strains ◽

Bacteria Growth ◽

Chemical Surface ◽

Titanium Surfaces ◽

Synthetic Coating

Here, titanium porous substrates were fabricated by a space holder technique. The relationship between microstructural characteristics (pore equivalent diameter, mean free-path between pores, roughness and contact surface), mechanical properties (Young’s modulus, yield strength and dynamic micro-hardness) and bacterial behavior are discussed. The bacterial strains evaluated are often found on dental implants: Methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. The colony-forming units increased with the size of the spacer for both types of studied strains. An antibiofouling synthetic coating based on a sulfonated polyetheretherketone polymer revealed an effective chemical surface modification for inhibiting MRSA adhesion and growth. These findings collectively suggest that porous titanium implants designed with a pore size of 100–200 µm can be considered most suitable, assuring the best biomechanical and bifunctional anti-bacterial properties.

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In-Situ Laser Directed Energy Deposition of Biomedical Ti-Nb and Ti-Zr-Nb Alloys from Elemental Powders

Metals ◽

10.3390/met11081205 ◽

2021 ◽

Vol 11 (8) ◽

pp. 1205

Author(s):

Felipe Arias-González ◽

Alejandra Rodríguez-Contreras ◽

Miquel Punset ◽

José María Manero ◽

Óscar Barro ◽

...

Keyword(s):

Mechanical Properties ◽

Corrosion Resistance ◽

Energy Deposition ◽

Titanium Implants ◽

Protective Oxide ◽

Directed Energy Deposition ◽

Protective Oxide Film ◽

Directed Energy ◽

Stable Passive

In order to achieve the required properties of titanium implants, more resources and research are needed to turn into reality the dream of developing the perfect implant material. The objective of this study was to evaluate the viability of the Laser Directed Energy Deposition to produce biomedical Ti-Nb and Ti-Zr-Nb alloys from elemental powders (Ti, Nb and Zr). The Laser Directed Energy Deposition is an additive manufacturing process used to build a component by delivering energy and material simultaneously. The material is supplied in the form of particles or wire and a laser beam is employed to melt material that is selectively deposited on a specified surface, where it solidifies. Samples with different compositions are characterized to analyze their morphology, microstructure, constituent phases, mechanical properties, corrosion resistance and cytocompatibility. Laser-deposited Ti-Nb and Ti-Zr-Nb alloys show no relevant defects, such as pores or cracks. Titanium alloys with lower elastic modulus and a significantly higher hardness than Ti grade 2 were generated, therefore a better wear resistance could be expected from them. Moreover, their corrosion resistance is excellent due to the formation of a stable passive protective oxide film on the surface of the material; in addition, they also possess outstanding cytocompatibility.

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Mechanical Properties of Electro-Discharge-Sintered Porous Titanium Implants

Korean Journal of Materials Research ◽

10.3740/mrsk.2006.16.3.173 ◽

2006 ◽

Vol 16 (3) ◽

pp. 173-177

Author(s):

C.Y. Hyun ◽

J.K. Huh ◽

W.H. Lee

Keyword(s):

Mechanical Properties ◽

Porous Titanium ◽

Titanium Implants

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Mechanical Properties of Porous Titanium Structure Fabricated by Investment Casting with Pressurization/Depressurization System

Korean Journal of Metals and Materials ◽

10.3365/kjmm.2014.52.3.203 ◽

2014 ◽

Vol 52 (3) ◽

pp. 203-209 ◽

Cited By ~ 3

Author(s):

San Kang ◽

Ji Woon Lee ◽

Soong Keun Hyun ◽

Byong Pil Lee ◽

Myoung Gyun Kim ◽

...

Keyword(s):

Mechanical Properties ◽

Investment Casting ◽

Porous Titanium ◽

Titanium Structure

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Dynamics of Nanoparticle Chain Aggregates of Carbon Under Tension

MRS Proceedings ◽

10.1557/proc-778-u4.4 ◽

2003 ◽

Vol 778 ◽

Author(s):

Rajdip Bandyopadhyaya ◽

Weizhi Rong ◽

Yong J. Suh ◽

Sheldon K. Friedlander

Keyword(s):

Mechanical Properties ◽

Carbon Black ◽

Polymer Film ◽

Elastic Behavior ◽

Small Strains ◽

Transmission Electron ◽

Chain Aggregates ◽

Nanoparticle Chains ◽

Reinforcing Filler

AbstractCarbon black in the form of nanoparticle chains is used as a reinforcing filler in elastomers. However, the dynamics of the filler particles under tension and their role in the improvement of the mechanical properties of rubber are not well understood. We have studied experimentally the dynamics of isolated nanoparticle chain aggregates (NCAs) of carbon made by laser ablation, and also that of carbon black embedded in a polymer film. In situ studies of stretching and contraction of such chains in the transmission electron microscope (TEM) were conducted under different maximum values of strain. Stretching causes initially folded NCA to reorganize into a straight, taut configuration. Further stretching leads to either plastic deformation and breakage (at 37.4% strain) or to a partial elastic behavior of the chain at small strains (e.g. 2.3% strain). For all cases the chains were very flexible under tension. Similar reorientation and stretching was observed for carbon black chains embedded in a polymer film. Such flexible and elastic nature of NCAs point towards a possible mechanism of reinforcement of rubber by carbon black fillers.

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Effect of Titanium Carbide Particles on Mechanical Properties of Aluminum Matrix Composites

Wasit Journal of Engineering Sciences ◽

10.31185/ejuow.vol5.iss2.55 ◽

2017 ◽

Vol 5 (2) ◽

pp. 20-30

Author(s):

Zaman Khalil Ibrahim

Keyword(s):

Mechanical Properties ◽

Titanium Carbide ◽

Compression Strength ◽

Volume Fraction ◽

Aluminum Matrix ◽

Aluminum Matrix Composites ◽

Matrix Composites ◽

Powder Metallurgy Technique ◽

Carbide Particles ◽

Properties Of Composites

In this research aluminum matrix composites (AMCs) was reinforced by titanium carbide (TiC) particles and was produced. Powder metallurgy technique (PM) has been used to fabricate AMCs reinforced with various amounts (0%, 4%, 8%, 12%, 16% and 20% volume fraction) of TiC particles to study the effect of different volume fractions on mechanical properties of the Al-TiC composites. Measurements of compression strength and hardness showed that mechanical properties of composites increased with an increase in volume fraction of TiC Particles. Al-20 % vol. TiC composites exhibited the best properties with hardness value (97HRB) and compression strength value (275Mpa).

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