scholarly journals EVALUATION OF THE SPACE HOLDERS TECHNIQUE APPLIED IN POWDER METALLURGY PROCESS IN THE USE OF TITANIUM AS BIOMATERIAL

2019 ◽  
Vol 49 (4) ◽  
pp. 261-268
Author(s):  
Ronei Tochetto ◽  
Rafael Tochetto ◽  
Luciano V. Biehl ◽  
J. L.B. Medeiros ◽  
J. C. Dos Santos ◽  
...  
Keyword(s):  
Powder Metallurgy ◽  
Titanium Powder ◽  
Bone Growth ◽  
Sufficient Conditions ◽  
Pure Titanium ◽  
Porous Metal ◽  
Metal Structure ◽  
Ammonium Bicarbonate ◽  
Commercially Pure Titanium ◽  
Powder Metallurgy Process

The objective of this paper is the manufacture of a porous metal structure from commercially pure titanium powder grade 1, aiming at the possible application as a biomaterial in the re-generation of bone tissues assuming its architecture. Exper-imental methods were used to evaluate the effectiveness of the use of the Space Holders tech-nique in the manufacture of powder metallurgy (MP). In the samples produced, 50% by volume of titanium powder and 50% of chemical reagent (So-dium Chloride - NaCl and Ammonium Bicarbonate - HN4HCO3) were added, compressed with a pressure of 250 Mpa. The metal-only test samples were com-pacted with pressures of 70 MPa and 250 MPa. The architecture found with the use of Space Holders was satisfactory, presenting sufficient conditions of size, morphology, and interconnectivity for bone growth within the structure. Samples made only with metal powder do not have enough pores even with lower compation pressure.

Study on selective laser melting of commercially pure titanium powder

2018 ◽  
Vol 233 (7) ◽  
pp. 1794-1807 ◽  
Author(s):  
Kurian Antony ◽  
T Reghunathan Rakeshnath
Keyword(s):  
Energy Density ◽  
Laser Power ◽  
Titanium Powder ◽  
Laser Energy ◽  
Pure Titanium ◽  
Commercially Pure Titanium ◽  
Laser Track ◽  
Laser Melting ◽  
Commercially Pure ◽  
Powder Particles

Laser additive manufacturing processes melt the powder particles using laser beam energy to form solid three-dimensional objects. This article mainly focuses on numerical analysis and experimentation of laser melting of commercially pure titanium powder. Numerical solutions to moving heat source problems were developed, and their influences on process parameters were validated. The energy density has a significant role in laser melting process. The numerical investigation demonstrates the significant effect of laser energy density on laser tracks. The laser power, distribution of powder particles, the absorptivity, density, and chemical constitution of powder materials are the main factors which influence the laser energy penetration. The absorptivity plays a vital role in consolidation phenomena of the powder layer which helps to get a denser part or layer. The experimental result clearly indicates that at lower laser speed the powder compaction is better. Temperature distribution, depth, and width of laser track were compared in this article. By investigating the observations from optical microscopic images and scanning electron microscopic images, the surface characteristics of laser-melted tracks were studied. The study on numerical and experimental results shows that the optimum condition for better laser track is laser power 45 W, laser speed 20 mm/s, and laser diameter 2.5 mm. This study provides important insights into laser parameters in the melting of commercially pure titanium powder.

Consolidation of Titanium Powder by Electrical Resistance Sintering: Practice and Simulation

2021 ◽  
Vol 876 ◽  
pp. 1-6
Author(s):  
Fátima Ternero Fernández ◽  
Petr Urban ◽  
Raquel Astacio Lopez ◽  
Rosa M. Aranda Louvier ◽  
Francisco G. Cuevas
Keyword(s):  
Electrical Resistance ◽  
Titanium Powder ◽  
Low Voltage ◽  
Pure Titanium ◽  
Commercially Pure Titanium ◽  
Consolidation Process ◽  
Simultaneous Application ◽  
Microhardness Distribution ◽  
Powder Mass ◽  
Furnace Sintering

In this work, a commercially pure titanium powder has been consolidated using the Electrical Resistance Sintering (ERS) process. This technique consists in the consolidation of a powder mass by the simultaneous application of pressure (80 MPa, in this work) and heating caused by the passage of a high intensity (3.5-6.0 kA, in this case) and low voltage current (lower than 10 V), during short dwelling times (0.8-1.6 s, in this work). The resulting compacts have been mechanically characterised by measuring their microhardness distribution. The results obtained are compared with the corresponding values of compacts prepared with the same powders following the conventional P/M route of cold pressing and furnace sintering. The results of some simulations are provided to give information about the temperatures reached inside the compacts during the electrical consolidation process.

Multi-Walled Carbon Nanotubes Reinforced Titanium Composites via Powder Metallurgy Process

2012 ◽  
Vol 520 ◽  
pp. 261-268 ◽  
Author(s):  
Katsuyoshi Kondoh ◽  
Thotsaphon Threrujirapapong ◽  
Sun Bin ◽  
Hisashi Imai ◽  
Shu Feng Li ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Tensile Strength ◽  
Powder Metallurgy ◽  
Titanium Powder ◽  
Fine Particles ◽  
Pure Titanium ◽  
Strengthening Effect ◽  
Composite Powders ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Un-bundled multi-walled carbon nanotubes (MWCNTs) were coated on titanium powder surface by using zwitterionic surfactant solution and mixing process, and their CNT/Ti composite powders were consolidated into full-dense materials by spark plasma sintering and the following hot extrusion process in solid-state. Wrought titanium powder metallurgy (PM) composites containing CNTs revealed extreme increment of yield stress and tensile strength of 85% and 50%, respectively, compared to conventional PM titanium with no reinforcement, while they had enough high ductility. The mechanical improvement was mainly due to dispersion strengthening effect of CNTs and in-situ formed TiC fine particles and a small mount of carbon solid solution into Ti matrix. In addition, the control of grain growth was promoted by TiC dispersoids during SPS, and contributed to their strengthening behavior. Furthermore, high-temperature tensile strength less than 673K of PM pure titanium materials was also obviously improved by the pinning effect of TiC particles dispersed at grain boundaries. In this paper, microstructural and mechanical properties of powder metallurgy titanium composites would be introduced in detail.

Development of Titanium Dental Implants Using Techniques of Powder Metallurgy

2014 ◽  
Vol 775-776 ◽  
pp. 13-18 ◽  
Author(s):  
Pâmela Karina dos Santos Bonfim ◽  
Ricardo Ciuccio ◽  
Maurício David Martins das Neves
Keyword(s):  
Corrosion Resistance ◽  
Powder Metallurgy ◽  
Biomedical Applications ◽  
Titanium Powder ◽  
Pure Titanium ◽  
High Reactivity ◽  
Titanium Implants ◽  
Vacuum Sintering ◽  
High Mechanical Strength ◽  
Titanium Dental Implants

Titanium is an attractive material for dental and biomedical applications, because of high corrosion resistance, excellent biocompatibility and high mechanical strength combined with low density. However, the high reactivity of titanium in the liquid phase make it difficult to produce it by fusion, so a alternative is powder metallurgy (P/M) method. Powder Metallurgy has been used to manufacture porous implants. The presence of a porous surface is desirable because it improves the osteointegration increases the adhesion between the bone tissue and the implant, being favorable for transporting body fluid. This paper proposes to characterize the commercial pure titanium powder obtained by process of hydride-dehydride, obtain samples with adequate porosity by uniaxial pressing and vacuum sintering and evaluate the corrosion behavior of sintered titanium in Hank ́s solution. The results showed that the titanium powder of angular shape after uniaxial pressing of 400 MPa and sintered in vacuum at 1150 ° C, allowed obtaining samples with adequate surface porosity of around 17%. In potentiodynamic polarization curves revealed no typical behavior of passive metals but show low current density, that increasing corrosion resistance. Keywords: titanium implants, powder metallurgy, porosity and electrochemical behavior.

Positron Annihilation Spectroscopy of Defects in Commercially Pure Titanium Saturated with Hydrogen

2014 ◽  
Vol 880 ◽  
pp. 134-140 ◽  
Author(s):  
Roman S. Laptev ◽  
Yuriy S. Bordulev ◽  
Viktor N. Kudiiarov ◽  
Andrey M. Lider ◽  
Georgy V. Garanin
Keyword(s):  
Gas Phase ◽  
Positron Lifetime ◽  
Pure Titanium ◽  
Metal Structure ◽  
Positron Annihilation Spectroscopy ◽  
Doppler Broadening ◽  
Commercially Pure Titanium ◽  
Commercially Pure ◽  
Hydrogen Interaction ◽  
Positron Lifetime Spectroscopy

The experimental study of the structure of commercially pure titanium after saturation with hydrogen from the gas phase by means of positron lifetime spectroscopy (PLS) and Doppler broadening spectroscopy (DBS) was carried out. In the result of penetration and accumulation of hydrogen, significant changes of annihilation characteristics occurred due to the defect structure changing. The investigated samples contained hydrogen in concentrations varying from 0 to 0.961 wt.%. Several stages of hydrogen interaction with the metal structure were revealed.

scholarly journals Sintering High Green Density Direct Powder Rolled Titanium Strips, in Argon Atmosphere

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 936
Author(s):  
Anthony Govender ◽  
Clinton Bemont ◽  
Silethelwe Chikosha
Keyword(s):  
Titanium Powder ◽  
High Vacuum ◽  
Pure Titanium ◽  
Batch Process ◽  
Commercially Pure Titanium ◽  
Green Density ◽  
Vacuum Sintering ◽  
Daily Production ◽  
Argon Gas ◽  
Air Contamination

Presently, the majority of titanium powder metallurgy components produced are sintered under high vacuum due to the associated benefits of the vacuum atmosphere. However, high-vacuum sintering is a batch process, which limits daily production. A higher daily part production is achievable via a continuous sintering process, which uses argon gas to shield the part from air contamination. To date, there has been limited work published on argon gas sintering of titanium in short durations. This study investigated the properties of thin high green density titanium strips, which were sintered at the temperatures of 1100 °C, 1200 °C and 1300 °C for a duration of 30 min, 60 min and 90 min in argon. The strips were produced by rolling of −45 µm near ASTM (American Society for Testing and Materials) grade 3 hydride–dehydride commercially pure titanium powder. The density, hardness, tensile properties and microstructure of the sintered strips were assessed. It was found that near-full densities, between 96 and 99%, are attainable after 30–90 min of sintering. The optimum sintering temperature range was found to be 1100–1200 °C, as this produced the highest elongation of 4–5.5%. Sintering at 1300 °C resulted in lower elongation due to higher contaminant pick-up.

Sign in / Sign up

Export Citation Format

Share Document