The effect of extension axis orientation on the localized plasticity in FCC single crystals

Using Co35Ni35Al30(at.%) single crystals the effects of crystals axis orientation and ageing at 673 K for 0.5 h in free state on superelasticity responses in compression are investigated. Ageing of these single crystals is found to result in strengthening of the high-temperature В2 phase and L10martensite, twofold increasing of temperature interval of SE response and weakening of the orientation dependence and improving the cycle stability of superelasticity response. In [011]- and [123]-oriented single crystals the values of the stress hysteresis decrease a nearly threefold as compared to the quenched state. The combination of high-strength [001] crystal axis orientation and precipitation of coherent nanoscale particles leads to the best stability of SE response in aged Co35Ni35Al30single crystals.

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Creep behavior of Ni3Ge single crystals of the deformation axis orientation [001]: Experiment and modeling

Bulletin of the Russian Academy of Sciences Physics ◽

10.3103/s1062873815110222 ◽

2015 ◽

Vol 79 (11) ◽

pp. 1364-1367

Author(s):

Yu. V. Solov’eva ◽

S. V. Starenchenko ◽

O. D. Pantyukhova ◽

V. A. Starenchenko

Keyword(s):

Single Crystals ◽

Creep Behavior ◽

Axis Orientation ◽

Deformation Axis

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Thermoelectric Properties of Magnetically c-axis Aligned Poly crystals in (Ca2ComOm+2δ)∼0.62Co02 (m=2 and 2) Systems

MRS Proceedings ◽

10.1557/proc-755-dd11.30 ◽

2002 ◽

Vol 755 ◽

Author(s):

S. Horii ◽

I. Matsubara ◽

M. Sano ◽

R. Funahashi ◽

M. Shikano ◽

...

Keyword(s):

Single Crystals ◽

Spark Plasma Sintering ◽

Thermoelectric Properties ◽

Magnetic Alignment ◽

Axis Orientation ◽

Plasma Sintering ◽

Axis Alignment ◽

Spark Plasma

ABSTRACTWe report preparation and thermoelectric properties of c-axis aligned and densified Ca3Co4O9 and [Ca2(Co0.65Cu0.35)2O4]0.624CoO2 polycrystals. The c-axis alignment and densification were accomplished by magnetic alignment and spark plasma sintering methods, respectively. The obtained samples showed high degrees of c-axis orientation and relative densities, which were close to those of single crystals, resulting in the highest values of power factors in Ca3Co4O9 and [Ca2(Co0.65Cu0.35)2O4]0.624CoO2 polycrystals.

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Thin Film Formation of Perovskite Type Dielectric and Ferroelectric Materials(MTiO3,M=Ca,Sr,Ba and Pb) by Pulsed Laser Deposition

MRS Proceedings ◽

10.1557/proc-361-533 ◽

1994 ◽

Vol 361 ◽

Cited By ~ 3

Author(s):

Hitoshi Tabata ◽

Hidekazu Tanaka ◽

Tomoji Kawai

Keyword(s):

Pulsed Laser Deposition ◽

Single Crystals ◽

Remanent Polarization ◽

Film Formation ◽

Pulsed Laser ◽

Dielectric Materials ◽

Ferroelectric Materials ◽

Laser Deposition ◽

Axis Orientation ◽

Perovskite Type

ABSTRACTWe have formed thin films of ferroelectric and dielectric materials (BaTiO3, SrTiO3 and CaTiO3) by pulsed laser deposition on various kinds of substrates such as SrTiO3, LaAlO3 and MgO(100) single crystals. All the films can be formed epitaxially on the SrTiO3 substrate with c-axis orientation by choosing suitable conditions. The electrical behavior of these films such as dielectric constant and spontaneous polarization is quite similar to that of single crystals in bulk samples. The remanent polarization of BaTiO3 and PbTiO3 films are about 15 μC/cm2 and 80 μC/cm2, respectively. The value of 80 μC/cm2 is almost the same as that theoretically predicted and have not been obtain in the bulk samples. The unique advantage of the pulsed laser deposition technique is its ability to produce highly oriented stoichiometric films that show good electrical properties.

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Crystallographic Control on the Development of Texture in Precipitated Quartz Grains

Materials Science Forum ◽

10.4028/www.scientific.net/msf.495-497.57 ◽

2005 ◽

Vol 495-497 ◽

pp. 57-62 ◽

Cited By ~ 1

Author(s):

Leonardo Lagoeiro ◽

Paola Ferreira ◽

Cristiane Castro

Keyword(s):

Single Crystals ◽

Shear Plane ◽

Shear Direction ◽

Quartz Crystals ◽

Axis Orientation ◽

Thin Sections ◽

Polycrystalline Aggregates ◽

Textural Data ◽

Plastic Process ◽

Quartz Aggregates

In this study we analysed microstructures and determined [c]-axis textures of quartz crystals in veins formed parallel to composition banding in naturally deformed iron oxide-quartz rocks. Only veins of few millimeters thick were sampled. These veins were formed in a regime of non-coaxial deformation under temperature of ~300°C. We made thin sections from rock slabs cut perpendicular to shear plane and parallel to shear direction. In thin sections veins are composed of large single quartz crystals of lens or rhomb-shaped blocks similar to s-porphyroclast systems. Lattice distortion (i.e. undulose extinction, gradual lattice banding and subgrain boundaries) occurs in single crystals as revealed by optical microscopy. Distortion was caused by slip of dislocations preferentially on basal planes. These are also planes along which microcracks developed. Distinct types of microcracks are individualized based on size, orientation and distribution of voids. Microcracrack voids are filled by polycrystalline quartz aggregates. In contrast to single crystals, these aggregates do not have any optical microstructure that might be related to crystal plastic process. Moreover grain size distribution are quite different from those related to dynamic recrystallized aggregates. Despite of that, polycrystalline quartz aggregates have strong [c]-axis preferred orientations. These orientations are similar to those of single crystals close to the microfracture walls. In large spaced voids c-axes orientation of quartz in polycrystalline aggregate have significant misorientation angles with respect to the single crystal [c]-axis orientation, reaching values up to 45° to the foliation plane (XY section of the finite strain). Based on microstructural and textural data we propose a mode for quartz [c]-axis texture development in both single crystals and polycrystalline aggregates that fill microcrack voids.

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Room temperature deformation of single crystals of Ti5Si3 with the hexagonal D88 structure investigated by micropillar compression tests

Scientific Reports ◽

10.1038/s41598-020-75007-7 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Kyosuke Kishida ◽

Takayoshi Fukuyama ◽

Takuto Maruyama ◽

Haruyuki Inui

Keyword(s):

Fracture Toughness ◽

Transition Metal ◽

Single Crystals ◽

Room Temperature ◽

Specimen Size ◽

Temperature Deformation ◽

Compression Tests ◽

Axis Orientation ◽

Plastic Deformation Behavior ◽

Micropillar Compression

Abstract Micropillar compression tests of Ti5Si3 single crystals were conducted at room temperature as a function of loading axis orientation and specimen size in order to investigate their room temperature plastic deformation behavior. Plastic flow by the operation of three deformation modes, {1$${\overline{1}}$$ 1 ¯ 00}[0001], {2$${\overline{1}}$$ 1 ¯ $${\overline{1}}$$ 1 ¯ 2} < 2$${\overline{1}}$$ 1 ¯ $${\overline{1}}$$ 1 ¯ $${\overline{3}}$$ 3 ¯ > and {1$${\overline{1}}$$ 1 ¯ 01} < 2$${\overline{1}}$$ 1 ¯ $${\overline{1}}$$ 1 ¯ $${\overline{3}}$$ 3 ¯ > slip were observed in [2$${\overline{2}}$$ 2 ¯ 05]-, [0001]- and [4$${\overline{3}}$$ 3 ¯ $${\overline{1}}$$ 1 ¯ 0]-oriented micropillar specimens deformed at room temperature, respectively. The CRSS values were evaluated to be very high above 2.7 GPa and were confirmed to increase up to about 6 GPa with the decrease in the specimen size. The fracture toughness values are evaluated to be 0.45 MPa m1/2 (notch plane // (0001)) and 0.73 MPa m1/2 (notch plane //(1$${\overline{1}}$$ 1 ¯ 00)) based on the results of micro-cantilever bend tests of chevron-notched specimens. The fracture toughness values are considerably lower than those for D8l-Mo5SiB2 and D8l-Nb5Si3 evaluated by the same method, indicating the inherent brittleness of binary Ti5Si3 compared to the other transition-metal silicides of the TM5Si3 type (TM: transition-metal).

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Effect of the Deformation Axis Orientation on the Strength of Dislocation Junctions in FCC Single Crystals

Russian Metallurgy (Metally) ◽

10.1134/s0036029518100117 ◽

2018 ◽

Vol 2018 (10) ◽

pp. 947-953

Author(s):

R. I. Kurinnaya ◽

M. V. Zgolich ◽

V. A. Starenchenko ◽

M. V. Matveev ◽

I. A. Zgolich ◽

...

Keyword(s):

Single Crystals ◽

Axis Orientation ◽

Deformation Axis

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Plastic Deformation Behavior of Ti5Si3 Single Crystals

MRS Proceedings ◽

10.1557/proc-1128-u09-06 ◽

2008 ◽

Vol 1128 ◽

Author(s):

Kyosuke Kishida ◽

Masakazu Fujiwara ◽

Norihiko L. Okamoto ◽

Katsushi Tanaka ◽

Haruyuki Inui

Keyword(s):

Single Crystals ◽

Deformation Behavior ◽

Shear Stresses ◽

Prism Slip ◽

Axis Orientation ◽

Pyramidal Slip ◽

Plastic Deformation Behavior ◽

Different Types ◽

Deformation Modes ◽

Loading Axis

AbstractDeformation behavior of binary stoichiometric Ti5Si3 single crystals was examined as a function of the loading axis orientation and temperature. Two different types of deformation modes, namely {1100}[0001] prism slip, {2112}1/3<2113> pyramidal slip were newly identified to be activated above 1300 °C depending on the loading axis orientation. Critical resolved shear stresses (CRSS) for the {1100}[0001] prism slip and {2112}1/3<2113> pyramidal slip were estimated to be about 130 MPa and 330 MPa at 1400 °C, respectively. The values of the CRSS for these two slip systems decrease monotonously with increasing the temperature.

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