Thermally activated flow in soft and hard regions: Getting information on work hardening strain and recovery strain from rate change tests

Wolfgang Blum, P. Eisenlohr, M. Prell, K. Durst

    Research output: Contribution to journalArticle

    • 3 Citations

    Abstract

    The investigation of thermally activated glide processes by stress reduction tests is reviewed. The tests reveal that two mechanisms of inelastic deformation are superimposed, namely dislocation glide connected with work hardening by defect storage and recovery strain related with relaxation of internal stresses and defect recovery. The coupling of the two is proposed to be modeled within the composite model. A new kind of transient testing is proposed that combines the conventional rate change test with an intermediate stress reduction. Its application to nanocrystalline Ni shows similarity of the main parameters of thermally activated dislocation glide and recovery strain found for conventional pure single and polycrystals: spacings of thermal obstacles in units of free dislocation spacing ≈ 1, back flow starting after ≈ 20 % stress reduction, similar magnitude of relative contribution and stress dependence of recovery strain.

    Original languageEnglish (US)
    Pages (from-to)199-205
    Number of pages7
    JournalKovove Materialy
    Volume53
    Issue number4
    DOIs
    StatePublished - 2015

    Profile

    Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing)
    Muscle Contraction
    Recovery
    Addison Disease
    Amino Acid Chloromethyl Ketones
    Defects
    Strain hardening
    Epimestrol
    Blood Stains
    Anthralin
    Carbamyl Phosphate
    Aminopyrine
    Genetic Engineering
    Polycrystals
    Hot Temperature
    Composite materials
    Residual stresses
    Testing

    Keywords

    • Activation area
    • Composite model
    • Dislocations
    • Recovery
    • Subgrain boundaries
    • Thermally activated flow

    ASJC Scopus subject areas

    • Materials Chemistry
    • Metals and Alloys
    • Mechanical Engineering
    • Mechanics of Materials

    Cite this

    Thermally activated flow in soft and hard regions : Getting information on work hardening strain and recovery strain from rate change tests. / Blum, Wolfgang; Eisenlohr, P.; Prell, M.; Durst, K.

    In: Kovove Materialy, Vol. 53, No. 4, 2015, p. 199-205.

    Research output: Contribution to journalArticle

    Blum, Wolfgang; Eisenlohr, P.; Prell, M.; Durst, K. / Thermally activated flow in soft and hard regions : Getting information on work hardening strain and recovery strain from rate change tests.

    In: Kovove Materialy, Vol. 53, No. 4, 2015, p. 199-205.

    Research output: Contribution to journalArticle

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