On the Relationship between Pseudoelasticity and Texture Evolution in Ti-26Nb-0.5Si Alloy

2007 ◽  
Vol 558-559 ◽  
pp. 1407-1411
Author(s):  
Won Yong Kim ◽  
Han Sol Kim
Keyword(s):  
Strain Hardening ◽  
Volume Fraction ◽  
Texture Evolution ◽  
Flow Behavior ◽  
High Stress ◽  
Two Stage ◽  
Β Phase ◽  
Three Phase ◽  
The Relationship ◽  
Strain Hardening Rate

Texture and cyclic tensile behavior of Ti-26Nb-0.5Si (denoted as atomic percent) alloys in which the microstructures were varied by quenching, cold rolling and recrystallization heat treatment were investigated in order to understand the relationship between pseudoelastic behavior and texture formation. Three phase mixtures consisting of bcc-structured β phase, orthorhombic structured α" phase and hcp-structured intermediate ω phase were characterized to display the constituent phases. The volume fraction of constituent phases was found to be insensitive to the given materials processing. Two-stage yielding, one at low stress with low strain hardening rate and the other one at high stress with high strain hardening rate, appeared to exhibit a characteristic flow behavior in the present alloys. It is revealed that stress-induced martensite transformation resulting in two-stage yielding was closely associated with pseudoelasticity. On the basis of texture analyses, we have suggested that pseudoelasticity of the present alloys is hindered by the development of {001}<110> rotated cube component.

scholarly journals Twinning and texture development in an extruded AM30 magnesium alloy during compressive deformation

2021 ◽  
Author(s):  
Dyuti Sarker
Keyword(s):  
Magnesium Alloy ◽  
Volume Fraction ◽  
Texture Evolution ◽  
Flow Behavior ◽  
True Strain ◽  
Compressive Strain ◽  
Extrusion Direction ◽  
Compressive Deformation ◽  
Strain Behavior ◽  
Loading Direction

This study was aimed at evaluating the microstructure, mechanical behavior and texture response of extruded AM30 magnesium alloy in uniaxial compression with special attention to the effect of compressive strain amount, sample orientation, loading direction, compressive prestrain, and annealing. Compressive deformation along the extrusion direction (ED) resulted in sigmoidal true stress-true strain behavior together with three distinct stages of strain hardening, due to the presence of two sets of basal textures {0001}<2110> and {0001}<1010>, with caxes aligned nearly parallel to the normal direction (ND) of the extruded plate which facilitated the occurrence of {1012} extension twinning. The effect of in-plane loading direction, i.e., 0°,15°, 30°, 45° from the ED on the compressive flow behavior was investigated, which revealed nearly constant yield and ultimate compressive strengths but with a remarkable increase of fracture strain compared to the ED sample. The effect of pre-strain along the ED on the formation of twinning and texture was investigated during re-compression along the ED, transverse direction (TD) and ND. In the two-step ED-ED compression, the disappearance of twin boundaries or the coalescence of twins via twin growth was observed. After pre-strain along the ED, re-compression along the TD showed two seemingly opposite phenomena, i.e., the formation of new twins and de-twinning to be coexistent due to the presence of multiple sets of textures after the first-step pre-straining. The de-twinning activity decreased and the texture weakening was achieved with increasing pre-strain in the ED while doing recompression along the ND at a constant strain amount. Texture measurements revealed that the c-axes of hcp unit cells were always rotated towards the compression direction, regardless of compression in the ED, TD or ND. The annealing temperature and time also had a pronounced effect on microstructure and texture evolution. With increasing annealing time, the twins in the pre-compressed samples were observed to disappear gradually, as demonstrated by a decreased volume fraction of twins and weakened texture which became more randomly distributed. As a result, during re-compression along the ED, fewer twin formation and less intense texture were observed, resulting in a significant increase of ductility.

The damage strain field analysis of triangular symmetrical composite eutectic

2016 ◽  
Vol 13 (1) ◽  
pp. 6-11 ◽  
Author(s):  
Zhihong Du ◽  
Xinhua Ni ◽  
Xiequan Liu ◽  
Cheng Chen
Keyword(s):  
Field Distribution ◽  
Strain Field ◽  
Volume Fraction ◽  
Composite Ceramic ◽  
Field Analysis ◽  
Content Type ◽  
Damage Behavior ◽  
Damage And Fracture ◽  
Three Phase ◽  
The Relationship

Purpose According to the microstructural characteristics of composite ceramic, the strain field distribution regularity of triangular symmetrical composite eutectic is obtained from the stress field distribution regularity of three-phase element in composite ceramic. In allusion to the damage of composite eutectic, it is introduced as a variable in this paper with the aim to determine the strain field distribution regularity of triangular symmetrical composite eutectic with damage behavior. Design/methodology/approach On the basis of the relationship between strain field and fiber inclusions volume fraction, the strain field of composite eutectic is analyzed. Findings The strain field of composite ceramic is distinctly dependent on the fiber inclusions volume fraction, fiber diameter and damage behavior of composite eutectic by quantitative analysis. The strain in matrix parallel to eutectic is the maximum linear strain and the main factor for the damage and fracture of eutectics. Originality/value The foundation of the strength research of composite eutectic is laid.

scholarly journals Microstructure and Mechanical Evolution of Cu-2.7Be Sheets via Annealing

Metals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 241
Author(s):  
Yang Liu ◽  
Qinwei Wang ◽  
Bingqing Yao ◽  
Daibo Zhu ◽  
Deshan Chen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Volume Fraction ◽  
Secondary Phases ◽  
Grain Sizes ◽  
Β Phase ◽  
Mechanical Evolution ◽  
Bcc Structure ◽  
Maximum Volume Fraction ◽  
Cold Rolled ◽  
The Relationship

The microstructure and mechanical properties of cold-rolled Cu-2.7Be sheets under various annealing processes and conditions were investigated in this research. The increased beryllium content in the Cu-2.7Be alloy facilitates the formation of brittle secondary phases. Consequently, the study highlights the functionality of annealed Cu-2.7Be alloys as more favorable dynodes than the traditionally used Cu-2.0Be alloys. The mechanism of recrystallization used for the transformation of Cu-2.7Be alloys was that of continuous static recrystallization (cSRX). Moreover, the relationship between the orientation of the β phases and that of the surrounding Cu-matrix was determined to be (111)α∥(110)β and (011)α∥(001)β. The β phase has a body-centered cubic (bcc) structure with a = b = c = 0.281 nm. The β phase undergoes a morphology transformation from primitive lath-shaped β particles to quadrangle-shaped β particles during the annealing process. Such transformations could potentially have an effect on the mechanical properties of Cu-2.7Be sheets. There was a noticeable decline in the yield strength of the Cu-2.7Be after annealing, and the samples annealed at 770 °C for 15 min achieved the elongation with deep and uniform dimples caused by suitable β particle sizes, appropriate grain sizes, and the maximum volume fraction of ∑3 boundaries.

Relationship between Microstructure and Mechanical Strength of Dental Semiprecious Alloys Subjected to Solution Treatment

2018 ◽  
Vol 941 ◽  
pp. 1105-1110
Author(s):  
Toshikazu Akahori ◽  
Tusbasa Mizuno ◽  
Mitsuo Niinomi ◽  
Hisao Fukui
Keyword(s):  
High Temperature ◽  
Mechanical Strength ◽  
Corrosion Potential ◽  
Volume Fraction ◽  
Solution Treatment ◽  
Silver Alloy ◽  
Hardening Mechanism ◽  
Cu Content ◽  
Β Phase ◽  
The Relationship

Silver alloy is one of semi-precious alloys for dental prosthesis, which has been applied remarkably in Japanese dental field. Ag-20Pd-17.7Cu-12Au alloy (G12), which was newly developed for commercial dental silver alloy, shows the unique hardening mechanism after a simple solution treatment (ST) at relatively high temperature. However, the relationship between ST at various temperature and the mechanical strength of G12 has not been investigated fully. Therefore, the relationship between ST and mechanical properties of G12 after ST at various temperatures was investigated systematically in this study. G12 subjected to ST at relatively high temperature of 1173 K is composed of three kinds of phases with Ag-rich α2 phase, Cu-rich α1 phase and β phase of Pd-Cu intermetallic compound. Although nominal melting point of G12 was around 1233 K, the high Cu concentration area like α1 phase was partially dissolved and then the α1, α2 and partial β phases re-precipitated during cooling. On the other hand, the microstructure of G12 aged at 673 K after ST at 1023 K (STA) was mainly composed of two kinds of phases with α2 and α1 phases with a small amount of β phase, which was a typical microstructure of STA. The Vickers hardness of G12 subjected to ST at 1173 K was identical to that of the same alloy subjected to STA although the tensile strength, fatigue limit and ductility deteriorated to some degrees. The corrosion potential of G12 changed drastically with the temperature of ST. The potential may have been increased by the decrease in the volume fraction of the α1 phase with relatively high Cu content.

scholarly journals Twinning and texture development in an extruded AM30 magnesium alloy during compressive deformation

2021 ◽  
Author(s):  
Dyuti Sarker
Keyword(s):  
Magnesium Alloy ◽  
Volume Fraction ◽  
Texture Evolution ◽  
Flow Behavior ◽  
True Strain ◽  
Compressive Strain ◽  
Extrusion Direction ◽  
Compressive Deformation ◽  
Strain Behavior ◽  
Loading Direction

This study was aimed at evaluating the microstructure, mechanical behavior and texture response of extruded AM30 magnesium alloy in uniaxial compression with special attention to the effect of compressive strain amount, sample orientation, loading direction, compressive prestrain, and annealing. Compressive deformation along the extrusion direction (ED) resulted in sigmoidal true stress-true strain behavior together with three distinct stages of strain hardening, due to the presence of two sets of basal textures {0001}<2110> and {0001}<1010>, with caxes aligned nearly parallel to the normal direction (ND) of the extruded plate which facilitated the occurrence of {1012} extension twinning. The effect of in-plane loading direction, i.e., 0°,15°, 30°, 45° from the ED on the compressive flow behavior was investigated, which revealed nearly constant yield and ultimate compressive strengths but with a remarkable increase of fracture strain compared to the ED sample. The effect of pre-strain along the ED on the formation of twinning and texture was investigated during re-compression along the ED, transverse direction (TD) and ND. In the two-step ED-ED compression, the disappearance of twin boundaries or the coalescence of twins via twin growth was observed. After pre-strain along the ED, re-compression along the TD showed two seemingly opposite phenomena, i.e., the formation of new twins and de-twinning to be coexistent due to the presence of multiple sets of textures after the first-step pre-straining. The de-twinning activity decreased and the texture weakening was achieved with increasing pre-strain in the ED while doing recompression along the ND at a constant strain amount. Texture measurements revealed that the c-axes of hcp unit cells were always rotated towards the compression direction, regardless of compression in the ED, TD or ND. The annealing temperature and time also had a pronounced effect on microstructure and texture evolution. With increasing annealing time, the twins in the pre-compressed samples were observed to disappear gradually, as demonstrated by a decreased volume fraction of twins and weakened texture which became more randomly distributed. As a result, during re-compression along the ED, fewer twin formation and less intense texture were observed, resulting in a significant increase of ductility.

scholarly journals Pore-Scale Simulation of Particle Flooding for Enhancing Oil Recovery

Energies ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2305
Author(s):  
Xiangbin Liu ◽  
Le Wang ◽  
Jun Wang ◽  
Junwei Su
Keyword(s):  
Oil Recovery ◽  
Flow Behavior ◽  
Ct Scanning ◽  
Water Flooding ◽  
Pore Scale ◽  
Simulation Techniques ◽  
Three Phase ◽  
Remaining Oil ◽  
Three Phase Flow ◽  
Displacement Force

The particles, water and oil three-phase flow behaviors at the pore scale is significant to clarify the dynamic mechanism in the particle flooding process. In this work, a newly developed direct numerical simulation techniques, i.e., VOF-FDM-DEM method is employed to perform the simulation of several different particle flooding processes after water flooding, which are carried out with a porous structure obtained by CT scanning of a real rock. The study on the distribution of remaining oil and the displacement process of viscoelastic particles shows that the capillary barrier near the location with the abrupt change of pore radius is the main reason for the formation of remaining oil. There is a dynamic threshold in the process of producing remaining oil. Only when the displacement force exceeds this threshold, the remaining oil can be produced. The flow behavior of particle–oil–water under three different flooding modes, i.e., continuous injection, alternate injection and slug injection, is studied. It is found that the particle size and the injection mode have an important influence on the fluid flow. On this basis, the flow behavior, pressure characteristics and recovery efficiency of the three injection modes are compared. It is found that by injecting two kinds of fluids with different resistance increasing ability into the pores, they can enter into different pore channels, resulting in the imbalance of the force on the remaining oil interface and formation of different resistance between the channels, which can realize the rapid recovery of the remaining oil.

scholarly journals Application of Artificial Intelligence and Gamma Attenuation Techniques for Predicting Gas–Oil–Water Volume Fraction in Annular Regime of Three-Phase Flow Independent of Oil Pipeline’s Scale Layer

Mathematics ◽  
2021 ◽  
Vol 9 (13) ◽  
pp. 1460
Author(s):  
Abdulaziz S. Alkabaa ◽  
Ehsan Nazemi ◽  
Osman Taylan ◽  
El Mostafa Kalmoun
Keyword(s):  
Gamma Radiation ◽  
Volume Fraction ◽  
Phase Flow ◽  
Gas Oil ◽  
Oil Pipeline ◽  
Intelligent Technique ◽  
Scale Layer ◽  
Three Phase ◽  
Three Phase Flow ◽  
Annular Regime

To the best knowledge of the authors, in former studies in the field of measuring volume fraction of gas, oil, and water components in a three-phase flow using gamma radiation technique, the existence of a scale layer has not been considered. The formed scale layer usually has a higher density in comparison to the fluid flow inside the oil pipeline, which can lead to high photon attenuation and, consequently, reduce the measuring precision of three-phase flow meter. The purpose of this study is to present an intelligent gamma radiation-based, nondestructive technique with the ability to measure volume fraction of gas, oil, and water components in the annular regime of a three-phase flow independent of the scale layer. Since, in this problem, there are several unknown parameters, such as gas, oil, and water components with different amounts and densities and scale layers with different thicknesses, it is not possible to measure the volume fraction using a conventional gamma radiation system. In this study, a system including a 241Am-133Ba dual energy source and two transmission detectors was used. The first detector was located diametrically in front of the source. For the second detector, at first, a sensitivity investigation was conducted in order to find the optimum position. The four extracted signals in both detectors (counts under photo peaks of both detectors) were used as inputs of neural network, and volume fractions of gas and oil components were utilized as the outputs. Using the proposed intelligent technique, volume fraction of each component was predicted independent of the barium sulfate scale layer, with a maximum MAE error of 3.66%.

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