Initial texture dependence of nanocrystalline omega phase formation during high pressure torsion of commercially pure titanium

2021 ◽  
Vol 802 ◽  
pp. 140687
Author(s):  
Subhasis Sinha ◽  
Vivek K. Sahu ◽  
Vikrant Beura ◽  
Reshma Sonkusare ◽  
Rajib Kalsar ◽  
...  
Keyword(s):  
High Pressure ◽  
Phase Formation ◽  
High Pressure Torsion ◽  
Pure Titanium ◽  
Commercially Pure Titanium ◽  
Omega Phase ◽  
Commercially Pure ◽  
Initial Texture

scholarly journals Slippage during high-pressure torsion of commercially pure titanium and application of accumulative HPT to it

2022 ◽  
Vol 1213 (1) ◽  
pp. 012003
Author(s):  
D V Gunderov ◽  
A A Churakova ◽  
A V Sharafutdinov ◽  
V D Sitdikov ◽  
V V Astanin
Keyword(s):  
High Pressure ◽  
High Pressure Torsion ◽  
Pure Titanium ◽  
Phase Changes ◽  
Phase Content ◽  
Commercially Pure Titanium ◽  
Micro Hardness ◽  
Ω Phase ◽  
Commercially Pure ◽  
First Time

Abstract A new efficient method was used to find that in the case of high-pressure torsion of commercially pure titanium, accumulation of shear strain in Ti does not occur due to slippage of anvils. Despite this, micro-hardness increases as the number of turns n increases, and Ti structure is refined more intensively. High-pressure torsion is accompanied by a high-pressure ω-phase formation. However, the content of ω-phase changes non-monotonously with an increase in the number of turns. First, while number of turns is less than n=5, the ω-phase content reaches 50%. Upon further deformation, the ω-phase content decreases to 15% for n=20. A new accumulative high-pressure torsion method is applied to commercially pure titanium for the first time. Accumulative high-pressure torsion leads to the strongest transformation of the structure and an increase in hardness, since stronger real deformation occurs due to composition of compression and torsion strain cycles.

scholarly journals Influence of Inhomogeneity on Mechanical Properties of Commercially Pure Titanium Processed by HPT

2018 ◽  
Vol 385 ◽  
pp. 284-289 ◽  
Author(s):  
Alexander P. Zhilyaev ◽  
Yi Huang ◽  
Jose María Cabrera ◽  
Terence G. Langdon
Keyword(s):  
Mechanical Properties ◽  
High Pressure Torsion ◽  
Structural Phase ◽  
Pure Titanium ◽  
High Strength ◽  
Alpha Phase ◽  
Commercially Pure Titanium ◽  
Omega Phase ◽  
Commercially Pure ◽  
Ti Powder

Already for fifteen years many researchers have been trying to discover metallic materials with unusual combinations of strength and ductility: with high strength and enhanced ductility. This combination may be achieved through different ways: alloying, nanostructuring, etc. This report is an attempt to analyze the influence of inhomogeneity of different types (structural, phase and space) on mechanical properties of commercially pure titanium (bulk and powder) subjected to high-pressure torsion. Experimental results for HPT bulk and powder titanium have demonstrated that mechanical behavior of CP titanium strongly depends on phase inhomogeneity (alpha + omega phases), structural inhomogeneity (bimodal grain size distribution) and space inhomogeneity (retained porosity) in case of cold consolidated Ti powder. High strength in HPT bulk titanium due to the formation of hard omega phase during HPT processing at room temperature was detected. The strong omega phase transforms back to nanograined alpha phase domains during short annealing at elevated temperature. HPT consolidation of titanium powder leads to the formation of brittle specimens showing high strength but almost zero plasticity.

scholarly journals High Pressure Torsion of Pure Ti: Effect of Pressure and Strain on Allotropy

2010 ◽  
Vol 89-91 ◽  
pp. 171-176 ◽  
Author(s):  
Kaveh Edalati ◽  
Z. Horita ◽  
Masaki Tanaka ◽  
Kenji Higashida
Keyword(s):  
High Pressure ◽  
Phase Formation ◽  
Bending Strength ◽  
High Pressure Torsion ◽  
Applied Pressure ◽  
Pure Titanium ◽  
Equivalent Strain ◽  
Bending Tests ◽  
Commercial Grade ◽  
Wide Range

High-pressure torsion (HPT) was conducted on commercial grade pure titanium (99.4%) by applying pressures in a wide range from 1.2 to 40 GPa. When the microhardness was plotted against equivalent strain, the hardness saturates to a constant level at each applied pressure. Such a level at the saturation depends on the applied pressure: for up to the pressure of 4 GPa, the saturation level is independent of the pressure but, for the pressures above 4 GPa, the hardness gradually increases with pressure because of the formation of an  phase. Bending tests showed that an excellent ductility as well as high bending strength was achieved for the sample processed at 2 GPa. The bending ductility was reduced for the sample at 6 GPa because of the  phase formation.

scholarly journals THE RESEARCH OF AGING AND MECHANICAL PROPERTIES OF NANOSTRUCTURAL TITANIUM

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.

RMI 0.2% Pd

Alloy Digest ◽  
1979 ◽  
Vol 28 (12) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Crevice Corrosion ◽  
Elevated Temperatures ◽  
Pure Titanium ◽  
Heat Treating ◽  
Low Ph ◽  
Commercially Pure Titanium ◽  
Bend Strength ◽  
Commercially Pure ◽  
Minimum Yield

Abstract RMI 0.2% Pd is a grade of commercially pure titanium to which up to 0.2% palladium has been added. It has a guaranteed minimum yield strength of 40,000 psi with good ductility and formability. It is recommended for corrosion resistance in the chemical industry and other places where the environment is mildly reducing or varies between oxidizing and reducing. The alloy has improved resistance to crevice corrosion at low pH and elevated temperatures. This datasheet provides information on composition, physical properties, elasticity, tensile properties, and bend strength. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: Ti-74. Producer or source: RMI Company.

UPM CP TITANIUM GRADE 3 (UNS R50550)

Alloy Digest ◽  
2020 ◽  
Vol 69 (6) ◽  
Keyword(s):  
Corrosion Resistance ◽  
Pure Titanium ◽  
Heat Treating ◽  
Commercially Pure Titanium ◽  
Commercially Pure ◽  
Continuous Service ◽  
Pure Grade ◽  
Grade 3 ◽  
Titanium Grade ◽  
Design Stress

Abstract UPM CP Titanium Grade 3 (UNS R50550) is an unalloyed commercially pure titanium that exhibits moderate strength (higher strength than that of Titanium Grade 2), along with excellent formability and corrosion resistance. It offers the highest ASME allowable design stress of any commercially pure grade of titanium, and can be used in continuous service up to 425 °C (800 °F) and in intermittent service up to 540 °C (1000 °F). This datasheet provides information on composition, physical properties, and elasticity. It also includes information on corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ti-167. Producer or source: United Performance Metals.

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