Mechanical properties and biological responses of ultrafine-grained pure titanium fabricated by multi-directional forging

Purpose: At present, materials research in the area of SPD (severe plastic deformation) processes is very intensive. Materials processed by these techniques show better mechanical properties and have finer grain when compared to the input feedstock. The refined microstructure may be ultrafine-grained or nanostructured, where the grain size becomes less than 100 nm. One of the materials used for such processes is CP (commercially pure) titanium of various grades, which is widely used for manufacturing dental implants. The article deals with one of the technologies available for the production of ultrafine-grained titanium: Conform technology. CP titanium processed by CONFORM technology exhibits improved mechanical properties and very favourable biocompatibility, due to its fine-grained structure. The article presents the current experience in the production of ultrafine CP titanium using this technology. The main objective of this article is describing the behaviour of CP titanium during forming in the Conform device and its subsequent use in dental implantology. Design/methodology/approach: In the present study, commercially pure Grade 2 titanium was processed using the CONFORM machine. The numerical simulation of the process was done using FEM method with DEFORMTM software. The evaluation was performed by simple tensile testing and transmission electron microscopy. The first conclusions were derived from the determined mechanical properties and based on analogies in available publications on a similar topic. Findings: This study confirmed that the SPD process improves mechanical properties and does not impair the ductility of the material. The CONFORM process enables the continuous production of ultrafine-grained or nanostructured materials. Research limitations/implications: At the present work, the results show the possible way of continuous production of ultrafine-grained or nanostructured materials. Nevertheless, the further optimization is needed in order to improve the final quality of wires and stabilize the process. As these factors will be solved, the technology will be ready for the industry. Practical implications: The article gives the practical information about the continuous production of ultrafine-grained pure titanium Grade 2 and the possibility of use this material for dental implants. Originality/value: The present paper gives information about the influence of the CONFORM technology on final mechanical and structural properties with the emphasis on technological aspects

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Biological responses of ultrafine grained pure titanium and their sand blasted surfaces

Materials Science and Engineering C ◽

10.1016/j.msec.2018.05.056 ◽

2018 ◽

Vol 91 ◽

pp. 382-388 ◽

Cited By ~ 11

Author(s):

Aslı Günay-Bulutsuz ◽

Özge Berrak ◽

H. Aygül Yeprem ◽

Elif Damla Arisan ◽

Mehmet Emin Yurci

Keyword(s):

Pure Titanium ◽

Biological Responses ◽

Ultrafine Grained

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Static mechanical properties and ductility of biomedical ultrafine-grained commercially pure titanium produced by ECAP process

Transactions of Nonferrous Metals Society of China ◽

10.1016/s1003-6326(17)60221-8 ◽

2017 ◽

Vol 27 (9) ◽

pp. 1964-1975 ◽

Cited By ~ 13

Author(s):

Reza NASERI ◽

Mehran KADKHODAYAN ◽

Mahmoud SHARIATI

Keyword(s):

Mechanical Properties ◽

Pure Titanium ◽

Commercially Pure Titanium ◽

Ecap Process ◽

Commercially Pure ◽

Ultrafine Grained ◽

Static Mechanical ◽

Static Mechanical Properties

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The Effect of Radial-Shear Rolling on the Microstructure and Mechanical Properties of Technical Titanium

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.299.565 ◽

2020 ◽

Vol 299 ◽

pp. 565-570

Author(s):

A. B. Naizabekov ◽

Sergey N. Lezhnev ◽

Alexandr S. Arbuz

Keyword(s):

Mechanical Properties ◽

Pure Titanium ◽

High Strength ◽

Grain Structure ◽

Work Piece ◽

Ultrafine Grained ◽

Alloying Additives ◽

Peripheral Areas ◽

Radial Shear Rolling

Improving the quality of hardware through the improvement of the microstructure is one of the main trends of modern metallurgy. This approach allows us to achieve special properties without the expense of expensive alloying additives. The basic idea is to grind the grain structure of the material to a size less than 1 μm. At the specified grain sizes, the hardening properties begin to manifest with a relatively small loss of plasticity. In this case, one can speak of ultrafine-grained (UFG) materials. This direction is especially important for areas of science and technology, where there are very strict requirements for the size and weight of parts with their high strength. These are aerospace engineering and medicine (implantology and orthopedics). Therefore, it makes sense to conduct research primarily on relevant materials. Titanium is known for its biological inertness, therefore it is the basis for prosthetics. In this work, the experiments on technically pure titanium using a technology close to industrial implementation, were performed. An experiment, in which a lengthy number billet at a temperature of 500 °C rolled from a diameter of 30 mm to a diameter of 15 mm in the mill SVP-08, was conducted. After that, the billet was cooled with water, and samples for studying the microstructure and samples for studying the mechanical properties, were prepared. Analysis of the microstructure showed the presence of an equiaxial ultrafine-grained structure in the peripheral areas of the work-piece and the presence of an elongated fibrous texture in the axial zone. The strength of the work-piece has increased by more than 1.5 times, while the plasticity has decreased not so much.

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Advanced mechanical properties of pure titanium with ultrafine grained structure

Scripta Materialia ◽

10.1016/s1359-6462(01)01089-2 ◽

2001 ◽

Vol 45 (7) ◽

pp. 747-752 ◽

Cited By ~ 254

Author(s):

A.V Sergueeva ◽

V.V Stolyarov ◽

R.Z Valiev ◽

A.K Mukherjee

Keyword(s):

Mechanical Properties ◽

Pure Titanium ◽

Ultrafine Grained Structure ◽

Ultrafine Grained

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THE RESEARCH OF AGING AND MECHANICAL PROPERTIES OF NANOSTRUCTURAL TITANIUM

Vektor nauki Tol yattinskogo gosudarstvennogo universiteta ◽

10.18323/2073-5073-2021-3-67-73 ◽

2021 ◽

pp. 67-73

Author(s):

L. R. Rezyapova ◽

◽

R. R. Valiev ◽

E. I. Usmanov ◽

R. Z. Valiev ◽

...

Keyword(s):

Mechanical Properties ◽

High Pressure Torsion ◽

Combined Treatment ◽

Pure Titanium ◽

Coarse Grained ◽

Second Phase ◽

Commercially Pure Titanium ◽

Commercially Pure ◽

Ultrafine Grained ◽

Pure Grade

It is known that titanium and its alloys are one of the promising materials in the industry, especially in medicine, due to their excellent biocompatibility and corrosion resistance. The latest modern equipment and instruments used in traumatology, orthopedics, dentistry, etc. demand increasingly higher mechanical properties for materials. In comparison with commercially pure titanium, alloys do not have such high corrosion-resistant properties and biocompatibility. In this regard, improving the mechanical characteristics of a pure material is an urgent issue. The authors studied the effect of annealing on the structure and properties of commercially pure grade 4 titanium in the coarse-grained and ultrafine-grained states. The ultrafine-grained state was obtained using high-pressure torsion (HPT) under the pressure of 6 GPa at N=10 revolutions at room temperature. In the microstructure investigated using transmission electron microscopy, the authors could detect particles of precipitated phases after annealing, which had different morphologies. Deformation leads to an increase in the precipitated particles after annealing. The authors carried out an X-ray phase analysis, which showed the approximation of the lattice parameters of the α-phase after deformation and annealing at 700 °C to the values of the parameters of pure titanium. Thus, aging processes occur in the material, accompanied by the decomposition of the supersaturated solid solution and the release of particles of the second phase. The paper shows the results of titanium microhardness measurements in different states. The combined treatment, consisting of HPT at N=5 revolutions, annealing at 700 °C, and additional HPT deformation at N=5 revolutions, allowed obtaining the record strength for commercially pure grade 4 titanium.

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Effect of thermomechanical treatment on the microstructures and mechanical properties of an ultrafine grained steel using bainite starting microstructure

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.3139/146.111771 ◽

2019 ◽

Vol 110 (6) ◽

pp. 517-523

Author(s):

Reza Gostariani ◽

Ahmad Kermanpur ◽

Abbas Najafizadeh

Keyword(s):

Mechanical Properties ◽

Thermomechanical Treatment ◽

Ultrafine Grained ◽

Microstructures And Mechanical Properties ◽

Ultrafine Grained Steel

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Mechanical Properties and Aging Behavior of Ultrafine Grained Al-Ag Alloy Fabricated by Accumulative Roll-Bonding

Materials Science Forum ◽

10.4028/www.scientific.net/msf.794-796.851 ◽

2014 ◽

Vol 794-796 ◽

pp. 851-856

Author(s):

Tadashiege Nagae ◽

Nobuhiro Tsuji ◽

Daisuke Terada

Keyword(s):

Mechanical Properties ◽

Grain Refinement ◽

Accumulative Roll Bonding ◽

Precipitation Hardening ◽

Tensile Elongation ◽

Solution Treatment ◽

High Strength ◽

Subsequent Aging ◽

Roll Bonding ◽

Ultrafine Grained

Accumulative roll-bonding (ARB) process is one of the severe plastic deformation processes for fabricating ultrafine grained materials that exhibit high strength. In aluminum alloys, aging heat treatment has been an important process for hardening materials. In order to achieve good mechanical properties through the combination of grain refinement hardening and precipitation hardening, an Al-4.2wt%Ag binary alloy was used in the present study. After a solution treatment at 550°C for 1.5hr, the alloy was severely deformed by the ARB process at room temperature (RT) up to 6 cycles (equivalent strain of 4.8). The specimens ARB-processed by various cycles (various strains) were subsequently aged at 100, 150, 200, 250°C, and RT. The hardness of the solution treated (ST) specimen increased by aging. On the other hand, hardness of the ARB processed specimen decreased after aging at high temperatures such as 250°C. This was probably due to coarsening of precipitates or/and matrix grains. The specimen aged at lower temperature showed higher hardness. The maximum harnesses achieved by aging for the ST specimen, the specimens ARB processed by 2 cycles, 4 cycles and 6 cycles were 55HV, 71HV, 69HV and 65HV, respectively. By tensile tests it was shown that the strength increased by the ARB process though the elongation decreased significantly. However, it was found that the tensile elongation of the ARB processed specimens was improved by aging without sacrificing the strength. The results suggest that the Al-Ag alloy having large elongation as well as high strength can be realized by the combination of the ARB process for grain refinement and the subsequent aging for precipitation hardening.

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