The Experts below are selected from a list of 16023 Experts worldwide ranked by ideXlab platform

Yurii V Voznyak - One of the best experts on this subject based on the ideXlab platform.

Victor A Beloshenko - One of the best experts on this subject based on the ideXlab platform.

F. Chen - One of the best experts on this subject based on the ideXlab platform.

  • Transformation hysteresis and Shape Memory Effect of an ultrafine-grained TiNiNb Shape Memory alloy
    Intermetallics, 2014
    Co-Authors: P. C. Jiang, B Tian, Dmitry V. Gunderov, Y X Tong, F. Chen, L J Li, Yanjun Zheng, Ruslan Z. Valiev
    Abstract:

    In present work, transformation hysteresis and Shape Memory Effect of an ultrafine-grained Ti44Ni47Nb9 alloy processed by ECAP were studied. After deformation, the ECAPed sample showed a much wider transformation hysteresis than the initial sample due to the enlarged strength mismatch between matrix and ??-Nb phase. The Shape Memory Effect and its cycling stability of the ECAPed sample were obviously improved. ?? 2014 Elsevier Ltd. All rights reserved.

  • Two-way Shape Memory Effect of TiNiSn alloys developed by martensitic deformation
    Materials Science and Engineering A-structural Materials Properties Microstructure and Processing, 2012
    Co-Authors: Yunxiang Tong, L. W. Ma, B Tian, F. Chen, Yufeng Zheng, Li Li, C.y. Chung
    Abstract:

    Abstract Two-way Shape Memory Effect of TiNiSn alloys was developed by martensite deformation. With increasing Sn content, two-way Shape Memory strain increased. A two-way Shape Memory strain of 0.83% was obtained in the Ti 56 Ni 38 Sn 6 alloy after 7.6% deformation. The dependence of Sn content on two-way Shape Memory Effect was discussed.

  • Two-way Shape Memory Effect of TiNiSn alloys developed by martensitic deformation
    Materials Science and Engineering A, 2012
    Co-Authors: Y X Tong, Baochun Guo, L. W. Ma, B Tian, F. Chen, L J Li, Yanjun Zheng, C.y. Chung
    Abstract:

    Two-way Shape Memory Effect of TiNiSn alloys was developed by martensite deformation. With increasing Sn content, two-way Shape Memory strain increased. A two-way Shape Memory strain of 0.83% was obtained in the Ti 56Ni 38Sn 6 alloy after 7.6% deformation. The dependence of Sn content on two-way Shape Memory Effect was discussed. © 2012 Elsevier B.V.

  • TRANSFORMATION BEHAVIOR AND Shape Memory Effect OF A CoAl ALLOY
    International Journal of Modern Physics B, 2009
    Co-Authors: F. Chen, B Tian, Yuxiang Tong, Yufeng Zheng
    Abstract:

    This paper investigates the microstructure, martensitic transformation and Shape Memory Effect of Co-16Al alloy. The optical micrographs of Co-16at.%Al alloy quenched from 1200°C show that the e martensite occurs at room temperature, while some remaining γ phase can also be observed. This microstructure analysis can be supported by XRD pattern. It is shown that the alloy undergoes a martensitic reverse transformation at about 220°C during heating. However, no transformation from the fcc phase to hcp phase is detected by DSC measurement upon cooling. It is thought that the precipitation of β phase by aging at high temperature may suppress the martensitic transformation. The tension strain is 12% and the fracture strength is above 800MPa. No obvious yield deformation is observed from the stress-strain curve. SEM images exhibits many dimples on the fracture surface, which means the fracture mechanism is ductile rupture. Bending test show that only 25% deformation can be recovered due to Shape Memory Effect w...

Sedigheh Farzaneh - One of the best experts on this subject based on the ideXlab platform.

  • EXPERIMENTAL INVESTIGATION ON THERMOPLASTIC POLYURETHANE HAVING PARTIAL Shape Memory Effect
    2020
    Co-Authors: Sofiane Abdallah-elhirtsi, Sedigheh Farzaneh, Joseph Fitoussi, Abbas Tcharkhtchi, B. J. Rashmi, Marie-france Lacrampe, Patricia Krawczak, Mines Douai
    Abstract:

    Summary: In the present work, a multi-cycles Shape Memory tests are performed on thermoplastic polyurethane (TPU) at 70°C which can regain only 67% of its initial Shape. This partial Shape Memory Effect (SME) has been improved by successive cycles of Shape Memory tests. After fourth cycles the polymer is able to regain 100% of its Shape. The results of fifth and sixth cycles confirm this modification. These original results indicate that a polymer with partial Shape Memory Effect may be transformed into a Shape Memory polymer without any chemical modification. This increase of Shape Memory Effect could be related to the creation of residual stresses during the tensile tests. The residual stresses are the origin of the driving force responsible for Shape Memory Effect.

  • Partial Shape Memory Effect of polymers
    2014
    Co-Authors: Abbas Tcharkhtchi, Joseph Fitoussi, S. Abdallah Elhirisia, K. M. Ebrahimi, Mohammadali Shirinbayan, Sedigheh Farzaneh
    Abstract:

    A blend of PLA (80%) and PBS (20%) has been prepared first by extrusion, then by injection molding. Tensile, stress-relaxation and recovery tests have been performed on the samples at 70°C and 75°C. The results indicated that the blend can regain only 24% of its initial Shape. This partial Shape Memory Effect has been improved by successive cycles of Shape Memory tests. After a fourth cycle, the blend is able to regain 82% of its Shape. These original results indicated that a polymer without (or with partial) Shape Memory Effect may be transformed to a Shape Memory polymer without any chemical modification.

  • Some New Concepts of Shape Memory Effect of Polymers
    Polymers, 2014
    Co-Authors: Abbas Tcharkhtchi, Joseph Fitoussi, Mohammadali Shirinbayan, Sofiane Abdallah-elhirtsi, Kambiz Ebrahimi, Sedigheh Farzaneh
    Abstract:

    In this study some new concepts regarding certain aspects related to Shape Memory polymers are presented. A blend of polylactic acid (PLA) (80%) and polybutylene succinate (PBS) (20%) was prepared first by extrusion, then by injection molding to obtain the samples. Tensile, stress-relaxation and recovery tests were performed on these samples at 70 °C. The results indicated that the blend can only regain 24% of its initial Shape. It was shown that, this partial Shape Memory Effect could be improved by successive cycles of Shape Memory tests. After a fourth cycle, the blend is able to regain 82% of its Shape. These original results indicated that a polymer without (or with partial) Shape Memory Effect may be transformed into a Shape Memory polymer without any chemical modification. In this work, we have also shown the relationship between Shape Memory and property Memory Effect. Mono and multi-frequency DMA (dynamic mechanical analyzer) tests on virgin and 100% recovered samples of polyurethane (PU) revealed that the polymer at the end of the Shape Memory tests regains 100% of its initial form without regaining some of its physical properties like glass transition temperature, tensile modulus, heat expansion coefficient and free volume fraction. Shape Memory (with and without stress-relaxation) tests were performed on the samples in order to show the role of residual stresses during recovery tests. On the basis of the results we have tried to show the origin of the driving force responsible for Shape Memory Effect.

V. N. Varyukhin - One of the best experts on this subject based on the ideXlab platform.

  • The Shape Memory Effect in polymers
    Russian Chemical Reviews, 2005
    Co-Authors: Victor A Beloshenko, V. N. Varyukhin, Yurii V Voznyak
    Abstract:

    The review concerns the state-of-the-art in the field of investigations of the Shape Memory Effect in various polymeric materials, namely, homopolymers, copolymers, polymer blends, filled polymer composites and polymer gels. New theoretical approaches to the description and practical applications of the Shape Memory Effect are discussed.

  • Shape-Memory Effect in Polymer Composites with a Compactible Filler
    Mechanics of Composite Materials, 2003
    Co-Authors: V. A. Beloshenko, A. P. Borzenko, Ya. E. Beigel’zimer, V. N. Varyukhin
    Abstract:

    The Shape-Memory Effect has been investigated in formed porous polymers and composites under heating. An epoxy polymer, ultrahigh-molecular polyethylene, and polypropylene were used as the polymeric matrix and carbon materials of different bulk density were taken for the filler. An unconventional Shape-Memory Effect, which is accompanied by an increase in volume, was created. Processing schemes by which this Effect can be achieved are proposed. They make it possible to obtain products of varying configuration.

  • Shape Memory Effect in the epoxy polymer–thermoexpanded graphite system
    Composites Part A-applied Science and Manufacturing, 2002
    Co-Authors: V. A. Beloshenko, Ya.e Beygelzimer, A. P. Borzenko, V. N. Varyukhin
    Abstract:

    Abstract The peculiarities of Shape recovery for deformed samples of the epoxy polymer–thermoexpanded graphite composition have been investigated. At specific concentrations of the filler, the Shape Memory Effect accompanied by a significant increase in volume is observed. A number of technological schemes for obtaining products with unconventional Shape Memory Effect and a physical model explaining the Effect and specifying the boundaries of the region where it could be realized are proposed.