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Yu. I. Chumlyakov - One of the best experts on this subject based on the ideXlab platform.
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Tension-compression asymmetry of the superelastic behavior of high-strength [001]-oriented FeNiCoAlNb crystals
Materials Letters, 2021Co-Authors: Yu. I. Chumlyakov, Irina Kireeva, I. V. Kuksgauzen, D. A. Kuksgauzen, Thomas Niendorf, P. KrooβAbstract:Abstract Temperature dependence of the stresses σcr of stress-induced γ-α′ martensitic transformations (MT) and superelasticity (SE) were studied in Tension and compression on [001]-oriented Fe-27Ni-17Co-11.7Al-2.9Nb (FeNiCoAlNb) (at.%) crystals after two-step ageing (973 K, 0.5 h + 723 K, 3h). It was shown that the α = dσcr/dT value does not depend on the stress State (Tension/compression) in the range of the stress-induced γ-α′ MT. SE depends on the stress State and the maximum SE strain of 11.5% was observed in compression.
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thermoelastic martensitic transformations in 011 oriented ni49fe18ga27co6 single crystals under Tension and compression loads
AIP Conference Proceedings, 2017Co-Authors: Elena Panchenko, Evgenevna Ekaterina Timofeeva, Aigerim Bauyrzhanovna Tokhmetova, Natalya Larchenkova, Nikita Surikov, Yu. I. ChumlyakovAbstract:The effect of the stress State (Tension/compression) on the thermoelastic L21-(10M,14M)-L10 martensitic transformations during heating/cooling cycles under constant tensile and compressive applied stress in [011]-oriented Ni49Fe18Ga27Co6 single crystals was determined. The martensitic transformation in cooling/heating occurs with a maximum reversible strain of 4.1% at a constant tensile stress of 50 MPa, and the value of the thermal hysteresis is independent of applied tensile stress. On the contrary, the value of thermal hysteresis increases by a factor of 4 with the growth of the external compressive stress level. The reversible strain 5.5% during cooling/heating cycles and a bursting character of reverse martensitic transformation at the compressive stress 60 MPa are observed. Such asymmetry of the properties in [011]-oriented Ni49Fe18Ga27Co6 single crystals at martensitic transformations is caused by the detwinning processes of L10-martensite crystals under compressive applied stress.
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Tension compression asymmetry of functional properties in 001 oriented ferromagnetic nifegaco single crystals
Intermetallics, 2010Co-Authors: Elena Panchenko, Yu. I. Chumlyakov, Hans Jürgen Maier, E. E. Timofeeva, Ibrahim KaramanAbstract:In the present study the effects of stress State (Tension/compression) and test temperature on the critical stress level for the stress-induced martensitic transformation, the shape memory effect and superelasticity of [001]-oriented Ni49Fe18Ga27Co6 (at.%) single crystals were investigated. It is shown that the strong Tension/compression asymmetry of the critical stress levels for the stress-induced martensitic transformation can be described by a modified Clausius–Clapreyron relationship, which takes the difference between the elastic moduli of austenite and martensite into account. The temperature interval in which superelasticity occurs and the reversible strain values associated with superelasticity and the shape memory effect are both strongly dependent on the stress State (Tension/compression). Moreover, the conditions necessary for the development of high-temperature superelasticity in Ni49Fe18Ga27Co6 single crystals have been determined. For the Ni49Fe18Ga27Co6 single crystals a large interval of superelasticity (315 K < T < 723 K) was obtained when the single crystals were loaded in Tension along the [001]-orientation.
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Tension/compression asymmetry of functional properties in [001]-oriented ferromagnetic NiFeGaCo single crystals
Intermetallics, 2010Co-Authors: Elena Panchenko, Yu. I. Chumlyakov, Hans Jürgen Maier, E. E. Timofeeva, Ibrahim KaramanAbstract:In the present study the effects of stress State (Tension/compression) and test temperature on the critical stress level for the stress-induced martensitic transformation, the shape memory effect and superelasticity of [001]-oriented Ni49Fe18Ga27Co6 (at.%) single crystals were investigated. It is shown that the strong Tension/compression asymmetry of the critical stress levels for the stress-induced martensitic transformation can be described by a modified Clausius–Clapreyron relationship, which takes the difference between the elastic moduli of austenite and martensite into account. The temperature interval in which superelasticity occurs and the reversible strain values associated with superelasticity and the shape memory effect are both strongly dependent on the stress State (Tension/compression). Moreover, the conditions necessary for the development of high-temperature superelasticity in Ni49Fe18Ga27Co6 single crystals have been determined. For the Ni49Fe18Ga27Co6 single crystals a large interval of superelasticity (315 K
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orientation dependence and Tension compression asymmetry of shape memory effect and superelasticity in ferromagnetic co40ni33al27 co49ni21ga30 and ni54fe19ga27 single crystals
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2008Co-Authors: Yu. I. Chumlyakov, Elena Panchenko, I V Kireeva, I Karaman, Huseyin Sehitoglu, H J Maier, A V Tverdokhlebova, A V OvsyannikovAbstract:Abstract In the present study the effects of crystal axis orientation, stress State (Tension/compression) and test temperature on shape memory effect and superelasticity of Ni54Fe19Ga27(I), Co40Ni33Al27(II), Co49Ni21Ga30(III) (numbers indicate at.%) single crystals were investigated. The shape memory effect, the start temperature of superelasticity T1 and the mechanical hysteresis Δσ were found to be dependent on crystal axis orientation and stress State. Superelasticity was observed at T1 = Af (Af, reverse transformation-finish temperature) in Tension/compression for [0 0 1]-oriented Ni–Fe–Ga crystals and in compression for [0 0 1]-oriented Co–Ni–Ga crystals, which all displayed a small mechanical hysteresis (Δσ ≤ 30 MPa). An increase in Δσ of up to 90 MPa in the Co–Ni–Al and the Co–Ni–Ga crystals lead to stabilization of the stress-induced martensite, and an increase in to T1 = Af + Δ. The maximal value of Δ (75 K) was found in [0 0 1]-oriented Co–Ni–Al crystals in Tension. A thermodynamic criterion describing the dependencies of the start temperature of superelasticity T1 on crystal axis orientation, stress State and the magnitude of mechanical hysteresis is discussed.
Elena Panchenko - One of the best experts on this subject based on the ideXlab platform.
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thermoelastic martensitic transformations in 011 oriented ni49fe18ga27co6 single crystals under Tension and compression loads
AIP Conference Proceedings, 2017Co-Authors: Elena Panchenko, Evgenevna Ekaterina Timofeeva, Aigerim Bauyrzhanovna Tokhmetova, Natalya Larchenkova, Nikita Surikov, Yu. I. ChumlyakovAbstract:The effect of the stress State (Tension/compression) on the thermoelastic L21-(10M,14M)-L10 martensitic transformations during heating/cooling cycles under constant tensile and compressive applied stress in [011]-oriented Ni49Fe18Ga27Co6 single crystals was determined. The martensitic transformation in cooling/heating occurs with a maximum reversible strain of 4.1% at a constant tensile stress of 50 MPa, and the value of the thermal hysteresis is independent of applied tensile stress. On the contrary, the value of thermal hysteresis increases by a factor of 4 with the growth of the external compressive stress level. The reversible strain 5.5% during cooling/heating cycles and a bursting character of reverse martensitic transformation at the compressive stress 60 MPa are observed. Such asymmetry of the properties in [011]-oriented Ni49Fe18Ga27Co6 single crystals at martensitic transformations is caused by the detwinning processes of L10-martensite crystals under compressive applied stress.
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Tension compression asymmetry of functional properties in 001 oriented ferromagnetic nifegaco single crystals
Intermetallics, 2010Co-Authors: Elena Panchenko, Yu. I. Chumlyakov, Hans Jürgen Maier, E. E. Timofeeva, Ibrahim KaramanAbstract:In the present study the effects of stress State (Tension/compression) and test temperature on the critical stress level for the stress-induced martensitic transformation, the shape memory effect and superelasticity of [001]-oriented Ni49Fe18Ga27Co6 (at.%) single crystals were investigated. It is shown that the strong Tension/compression asymmetry of the critical stress levels for the stress-induced martensitic transformation can be described by a modified Clausius–Clapreyron relationship, which takes the difference between the elastic moduli of austenite and martensite into account. The temperature interval in which superelasticity occurs and the reversible strain values associated with superelasticity and the shape memory effect are both strongly dependent on the stress State (Tension/compression). Moreover, the conditions necessary for the development of high-temperature superelasticity in Ni49Fe18Ga27Co6 single crystals have been determined. For the Ni49Fe18Ga27Co6 single crystals a large interval of superelasticity (315 K < T < 723 K) was obtained when the single crystals were loaded in Tension along the [001]-orientation.
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Tension/compression asymmetry of functional properties in [001]-oriented ferromagnetic NiFeGaCo single crystals
Intermetallics, 2010Co-Authors: Elena Panchenko, Yu. I. Chumlyakov, Hans Jürgen Maier, E. E. Timofeeva, Ibrahim KaramanAbstract:In the present study the effects of stress State (Tension/compression) and test temperature on the critical stress level for the stress-induced martensitic transformation, the shape memory effect and superelasticity of [001]-oriented Ni49Fe18Ga27Co6 (at.%) single crystals were investigated. It is shown that the strong Tension/compression asymmetry of the critical stress levels for the stress-induced martensitic transformation can be described by a modified Clausius–Clapreyron relationship, which takes the difference between the elastic moduli of austenite and martensite into account. The temperature interval in which superelasticity occurs and the reversible strain values associated with superelasticity and the shape memory effect are both strongly dependent on the stress State (Tension/compression). Moreover, the conditions necessary for the development of high-temperature superelasticity in Ni49Fe18Ga27Co6 single crystals have been determined. For the Ni49Fe18Ga27Co6 single crystals a large interval of superelasticity (315 K
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orientation dependence and Tension compression asymmetry of shape memory effect and superelasticity in ferromagnetic co40ni33al27 co49ni21ga30 and ni54fe19ga27 single crystals
Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2008Co-Authors: Yu. I. Chumlyakov, Elena Panchenko, I V Kireeva, I Karaman, Huseyin Sehitoglu, H J Maier, A V Tverdokhlebova, A V OvsyannikovAbstract:Abstract In the present study the effects of crystal axis orientation, stress State (Tension/compression) and test temperature on shape memory effect and superelasticity of Ni54Fe19Ga27(I), Co40Ni33Al27(II), Co49Ni21Ga30(III) (numbers indicate at.%) single crystals were investigated. The shape memory effect, the start temperature of superelasticity T1 and the mechanical hysteresis Δσ were found to be dependent on crystal axis orientation and stress State. Superelasticity was observed at T1 = Af (Af, reverse transformation-finish temperature) in Tension/compression for [0 0 1]-oriented Ni–Fe–Ga crystals and in compression for [0 0 1]-oriented Co–Ni–Ga crystals, which all displayed a small mechanical hysteresis (Δσ ≤ 30 MPa). An increase in Δσ of up to 90 MPa in the Co–Ni–Al and the Co–Ni–Ga crystals lead to stabilization of the stress-induced martensite, and an increase in to T1 = Af + Δ. The maximal value of Δ (75 K) was found in [0 0 1]-oriented Co–Ni–Al crystals in Tension. A thermodynamic criterion describing the dependencies of the start temperature of superelasticity T1 on crystal axis orientation, stress State and the magnitude of mechanical hysteresis is discussed.
Ibrahim Karaman - One of the best experts on this subject based on the ideXlab platform.
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Tension compression asymmetry of functional properties in 001 oriented ferromagnetic nifegaco single crystals
Intermetallics, 2010Co-Authors: Elena Panchenko, Yu. I. Chumlyakov, Hans Jürgen Maier, E. E. Timofeeva, Ibrahim KaramanAbstract:In the present study the effects of stress State (Tension/compression) and test temperature on the critical stress level for the stress-induced martensitic transformation, the shape memory effect and superelasticity of [001]-oriented Ni49Fe18Ga27Co6 (at.%) single crystals were investigated. It is shown that the strong Tension/compression asymmetry of the critical stress levels for the stress-induced martensitic transformation can be described by a modified Clausius–Clapreyron relationship, which takes the difference between the elastic moduli of austenite and martensite into account. The temperature interval in which superelasticity occurs and the reversible strain values associated with superelasticity and the shape memory effect are both strongly dependent on the stress State (Tension/compression). Moreover, the conditions necessary for the development of high-temperature superelasticity in Ni49Fe18Ga27Co6 single crystals have been determined. For the Ni49Fe18Ga27Co6 single crystals a large interval of superelasticity (315 K < T < 723 K) was obtained when the single crystals were loaded in Tension along the [001]-orientation.
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Tension/compression asymmetry of functional properties in [001]-oriented ferromagnetic NiFeGaCo single crystals
Intermetallics, 2010Co-Authors: Elena Panchenko, Yu. I. Chumlyakov, Hans Jürgen Maier, E. E. Timofeeva, Ibrahim KaramanAbstract:In the present study the effects of stress State (Tension/compression) and test temperature on the critical stress level for the stress-induced martensitic transformation, the shape memory effect and superelasticity of [001]-oriented Ni49Fe18Ga27Co6 (at.%) single crystals were investigated. It is shown that the strong Tension/compression asymmetry of the critical stress levels for the stress-induced martensitic transformation can be described by a modified Clausius–Clapreyron relationship, which takes the difference between the elastic moduli of austenite and martensite into account. The temperature interval in which superelasticity occurs and the reversible strain values associated with superelasticity and the shape memory effect are both strongly dependent on the stress State (Tension/compression). Moreover, the conditions necessary for the development of high-temperature superelasticity in Ni49Fe18Ga27Co6 single crystals have been determined. For the Ni49Fe18Ga27Co6 single crystals a large interval of superelasticity (315 K
Liliam Fernandes De Oliveira - One of the best experts on this subject based on the ideXlab platform.
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an 8 week resistance training protocol is effective in adapting quadriceps but not patellar tendon shear modulus measured by shear wave elastography
PLOS ONE, 2019Co-Authors: Pietro Mannarino, Thiago Torres Da Matta, Liliam Fernandes De OliveiraAbstract:Habitual loading and resistance training (RT) can lead to changes in muscle and tendon morphology as well as in its mechanical properties which can be measured by Shear Wave Elastography (SWE) technique. The objective of this study was to analyze the Vastus Lateralis (VL) and patellar tendon (PT) mechanical properties adaptations to an 8-week RT protocol using SWE. We submitted 15 untrained health young men to an 8-week RT directed for knee extensor mechanism. VL and PT shear modulus (μ) were assessed pre and post intervention with SWE. PT thickness (PTT), VL muscle thickness (VL MT) and knee exTension torque (KT) were also measure pre and post intervention to ensure the RT efficiency. Significant increases were observed in VL MT and KT (pre = 2.40 ± 0.40 cm and post = 2.63 ± 0.35 cm, p = 0.0111, and pre = 294.66 ± 73.98 Nm and post = 338.93 ± 76.39 Nm, p = 0.005, respectively). The 8-week RT was also effective in promoting VL μ adaptations (pre = 4.87 ± 1.38 kPa and post = 9.08.12 ± 1.86 kPa, p = 0.0105), but not in significantly affecting PT μ (pre = 78.85 ± 7.37 kPa and post = 66.41 ± 7.25 kPa, p = 0.1287) nor PTT (baseline = 0.364 ± 0.053 cm and post = 0.368 ± 0.046 cm, p = 0.71). The present study showed that an 8-week resistance training protocol was effective in adapting VL μ but not PT μ. Further investigation should be conducted with special attention to longer interventions, to possible PT differential individual responsiveness and to the muscle-tendon resting State Tension environment.
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an 8 week resistance training protocol is effective in adapting quadriceps but not patellar tendon shear modulus measured by supersonic shearwave imaging
bioRxiv, 2018Co-Authors: Pietro Mannarino, Thiago Torres Da Matta, Liliam Fernandes De OliveiraAbstract:Habitual loading and resistance training (RT) can determine changes in muscle and tendon morphology but also in its mechanical properties. Conventional ultrasound (US) evaluation of these mechanical properties present limitations that can now be overcome with the advent of Supersonic Shearwave Imaging (SSI). The objective of this study was to analyze the Vastus Lateralis (VL) and patellar tendon (PT) mechanical properties adaptations to an 8-week RT protocol using SSI. We submitted 15 untrained health young men to an 8-week RT directed knee extensor mechanism. VL and PT shear modulus ({micro}) was assessed pre and post intervention with SSI. VL muscle thickness (VL MT) and knee exTension torque (KT) was also measure pre and post intervention to ensure the RT efficiency. Significant increases were observed in VL MT and KT (pre= 2.40 {+/-} 0.40 cm and post= 2.63 {+/-} 0.35 cm, p = 0.0111, and pre= 294.66 {+/-} 73.98 Nm and post= 338.93 {+/-} 76.39 Nm, p = 0.005, respectively). The 8-week RT was also effective in promoting VL {micro} adaptations (pre= 4.87 {+/-} 1.38 kPa and post= 9.08.12 {+/-} 1.86 kPa, p = 0.0105), but not in significantly affecting PT {micro} (pre= 78.85 {+/-} 7.37 kPa and post= 66.41 {+/-} 7.25 kPa, p = 0.1287). The present study showed that an 8-week resistance training protocol was effective in adapting VL {micro} but not PT {micro}. Further investigation should be conducted with special attention to longer interventions, to possible PT differential individual responsiviness and to the muscle-tendon resting State Tension environment.
Richard L. Moss - One of the best experts on this subject based on the ideXlab platform.
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Onset of Reduced Ca2+Sensitivity of Tension During Stunning in Porcine Myocardium
Journal of molecular and cellular cardiology, 1996Co-Authors: William P. Miller, Kerry S. Mcdonald, Richard L. MossAbstract:Recent data suggest that reduced Ca2+sensitivity of Tension is a mechanism of the post-ischemic myocardial dysfunction, termed stunning. The purpose of the present study was to determine whether the decrease in myofilament Ca2+sensitivity occurs during ischemia or during the subsequent period of reperfusion. Serial biopsies from anin vivoopen-chest porcine model of regional LAD myocardial stunning (n=6) were used to obtainin vitromeasurements of Ca2+sensitivity of Tension in myocardium from the LAD bed. Regional ventricular myocardial function was assessed from percentage systolic myocardial wall thickening (%Th) and the load-independent end-systolic pressure wall thickness relation (ESPTR). Stunning was induced by 45 min of low flow LAD ischemia (43±4 ml/min/100 gm) followed by 30 min of reperfusion with control aerobic flow (117±7 ml/min/100 g). Endocardial biopsies were obtained from the LAD bed during pre-ischemia, ischemia (immediately prior to reperfusion), and post-ischemia (after 30 min of reperfusion). Biopsies were mechanically disrupted and single cell-sized preparations of permeabilized myocardium were attached to a force transducer to measure directly steady-State Tension-pCa relationships. The %Th decreased to 7±11% of control during ischemia (P
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Altered calcium sensitivity of isometric Tension in myocyte-sized preparations of porcine postischemic stunned myocardium.
Circulation research, 1993Co-Authors: Polly A. Hofmann, William P. Miller, Richard L. MossAbstract:Postischemic ventricular myocardial dysfunction, termed stunning, is characterized by a persistent but ultimately reversible depression of contractile function. The present study was undertaken to investigate the possibilities that reduced contractile force in stunning is due to a decrease in maximal Tension-generating capability or to a decrease in the Ca2+ sensitivity of the myofilaments. The experiments combine an in vivo open-chest porcine heart model of stunning (n = 5) with in vitro measures of myocyte myofilament calcium sensitivity from these same hearts. Regional myocardial function in the left anterior descending coronary artery (LAD) perfusion bed of porcine hearts was measured with transmural ultrasonic crystals. The protocol was 45 minutes of low-flow LAD ischemia at 40% of control flow, followed by 30 minutes of postischemic reperfusion at control aerobic flow. Percent systolic wall thickening decreased to 8 +/- 5% of control during ischemia (p < 0.05) and returned to 38 +/- 8% of control in the postischemic stunned State (p < 0.05). Serial endocardial biopsies were obtained from the preischemic and postischemic myocardium in the LAD perfusion bed and from the aerobically perfused myocardium in the circumflex bed. The biopsies were mechanically disrupted, and myocyte-sized preparations of permeabilized myocardium were attached to a force transducer and a length-changing device to allow for direct measurement of steady-State Tension-pCa (i.e., -log[Ca2+]) relations. The pCa for half-maximal activation of Tension, i.e., pCa50, in LAD myocardium decreased from 5.88 +/- 0.05 before ischemia to 5.69 +/- 0.03 after ischemia (p < 0.05); however, maximal Ca(2+)-activated Tension and the slope of the Tension-pCa relation were unaffected by the ischemic episode.(ABSTRACT TRUNCATED AT 250 WORDS)