Stored energy and electrical resistivity in deformed metals

Clarebrough, L. M.; Hargreaves, Mark; Loretto, M. H.

doi:10.1080/14786436108238374

Cited by 48 publications

(7 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…2(d) ). This observation is consistent with very careful calorimetric work on pure copper 19 20 21 22 31 . Our previous research has shown clean NT structure and few dislocations in as-deposited NT Cu 5 .…”

Section: Resultssupporting

confidence: 85%

“…We speculate that a high density of HABs and TJs would disturb the thermal stability of any CTBs in the vicinity. Few investigations have been conducted on the kinetics of recovery and recrystallization in NT Cu, though some work has been carried out on the HAG Cu 17 18 19 20 21 22 . This paper reports our studies of the kinetics of recovery and recrystallization of NT Cu.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Influence of grain boundary characteristics on thermal stability in nanotwinned copper

Niu

Han

et al. 2016

Sci Rep

View full text Add to dashboard Cite

High density grain boundaries provide high strength, but may introduce undesirable features, such as high Fermi levels and instability. We investigated the kinetics of recovery and recrystallization of Cu that was manufactured to include both nanotwins (NT) and high-angle columnar boundaries. We used the isothermal Johnson-Mehl-Avrami-Kolmogorov (JMAK) model to estimate activation energy values for recovery and recrystallization and compared those to values derived using the non-isothermal Kissinger equation. The JMAK model hinges on an exponent that expresses the growth mechanism of a material. The exponent for this Cu was close to 0.5, indicating low-dimensional microstructure evolution, which is associated with anisotropic twin coarsening, heterogeneous recrystallization, and high stability. Since this Cu was of high purity, there was a negligible impurity-drag-effect on boundaries. The twin coarsening and heterogeneous recrystallization resulted from migration of high-angle columnar boundaries with their triple junctions in one direction, assisted by the presence of high concentration vacancies at boundaries. Analyses performed by electron energy loss spectroscopy of atomic columns at twin boundaries (TBs) and in the interior showed similar plasma peak shapes and L3 edge positions. This implies that values for conductivity and Fermi level are equal for atoms at TBs and in the interior.

show abstract

Section: Resultssupporting

confidence: 85%

mentioning

confidence: 99%

Influence of grain boundary characteristics on thermal stability in nanotwinned copper

Niu

Han

et al. 2016

Sci Rep

View full text Add to dashboard Cite

show abstract

“…The quadrupole interaction of probes with EFG produced by dislocations (equation ( 3)) are presented in figure 2 as functions of V% Each v(d) in figure 2 for a given deformation is taken as the average value of the data from the initial flat region of the corresponding annealing curve v$) (Tan,) (see figure 3). Dislocation density values c were deduced from the degree of deformation E obtained from the interpolation of the results reported in [25,26]. The linear dependence of v g ) on the square root of the dislocation density is observed; however the uncertainty in the determination of dislocation density c must be considered.…”

Section: A4ffg2(t) =A;ff [(L -F>zs2n Cos Nmentioning

confidence: 99%

TDPAC studies on the recovery of Ag plastically deformed at room temperature

Wodniecka

Marszałek

Wodniecki

1989

J. Phys.: Condens. Matter

View full text Add to dashboard Cite

The recovery of polycrystalline silver rolled at room temperature to different degrees of deformation (33, 48, 73 and 95%) was investigated by means of the TDPAC technique with a 111Cd probe. The dependence of quadrupole interaction parameters, extracted from time spectra, on the degree of deformation and annealing temperature was studied. At temperatures in the range 350-425 K the recovery stage occurs which is indicated by the decrease of quadrupole interaction. For lower degrees of deformation also a small fraction ( approximately 2%) of sharp quadrupole frequency of 38(1) MHz was detected after annealing at temperatures 300-375 K, associated with vacancy complexes trapped on probe atoms.

show abstract

“…Measurement of various properties (electrical resistivity [10], internal friction [11], thermal expansion [12])have shown the occurrence of this phenomenon in a wide temperature range. These methods are however difficult or impossible to perform on deformed specimens and X-ray or neutron scattering experiments have failed to provide any direct evidence of SRO in a-brass owing to the similarity of scattering factor of copper and zinc atoms.…”

Section: Study Of Sro In Cu-zn Alloysmentioning

confidence: 99%

Thermoelectroc Power for Phase Transformation Study in Metallic Alloys

Borrelly¹,

Merle²,

Merlin³

et al. 1982

MRS Proc.

View full text Add to dashboard Cite

Recent experiments have proved the efficiency of T.E.P. measurements in phase transformation studies. The main features of the technique are presented and two particular examples of application are given (influence of plastic deformation on short range ordering (S.R.O.) and study of dissolution of the equilibrium 0 phase in Al-Cu alloys).Since the first studies [1] only very few attempts have been made to use thermoelectrical power measurements (T.E.P.) to characterize the evolution of an alloy during phase transformation. However, in spite of the complexity of the theoretical interpretations, T.E.P. measurements can give valuable informations on the microstructure of the material, sometimes with more easiness or more precision than with other techniques or even informations which would be impossible to obtain by another way.EXPERIMENTAL METHOD AND MAIN FEATURES OF T.E.P. Fig. 1 gives the principle of T.E.P. measurements. Two metallic reference blocks a and b with a good thermal conductivity (Al or Cu) are respectively maintained at temperatures T and T + AT. The sample is pressed on these blocks so as to ensure a good thermal and electrical contact. The junction with a manovoltmeter is realized with wires of the same metal as the reference blocks. If the voltage measured is Av, the relative thermoelectric power LS of the sample respective to the metal constitutive of the reference blocks is AS AV (1) AT and S = S + AS (2) s r if S and S are the absolute thermopower of the reference metal and of the sampfe. s The absolute thermopower depends on temperature [2]. Owing to this influence, the smallest temperature gradient AT compatible with a sufficient accuracy onAv is necessary to obtain a value of AS representative of the isothermal value at T T AT/2. In our case present measurements have been performed at a mean temperature of 20 0 C with AT = 10 0 C. For the study of phase transformations it is necessary to know the influence of some microstructural parameters on T.E.P. a) Influence of elements in solid solution : elements in solid solution modify the electric properties of the alloy and so the T.E.P. The contribution of elements in solid solution can be expressed at high temperature (when the diffuslonal component Sd of thermopower is predominant [2])) and under some simplifying assumptions L3] by p AS = p (s-s°) = a c. C. (s.-S) (3) 0 j J1 with P = P + Z i j. C. (4) 0 3 J J Mat. Res. Soc. Symp. Proc. Vol. 21 (1984) Q Elsevier Science Publishing Co., Inc.

show abstract

Stored energy and electrical resistivity in deformed metals

Cited by 48 publications

References 9 publications

Influence of grain boundary characteristics on thermal stability in nanotwinned copper

Influence of grain boundary characteristics on thermal stability in nanotwinned copper

TDPAC studies on the recovery of Ag plastically deformed at room temperature

Thermoelectroc Power for Phase Transformation Study in Metallic Alloys

Contact Info

Product

Resources

About