Low-temperature Plastic Deformation Research Articles

Mechanism of low-temperature plastic deformation in structural steel

It has been discovered that grade 30KhGSA steel after a high-temperature thermomechanical treatment is more plastic at −196°C than at room temperature, unlike in the case of quenched steel and uncharacteristically for metals or alloys with a bcc crystal lattice. A study has, therefore, been made to establish the temperature characteristic of the resistance to deformation and, especially, to its reversible component, both after an anneal and after a heat treatment of steel. The activation energy and volume of the thermally induced deformation were measured, whereupon the results were analyzed on the basis of the Payerls mechanism with dislocations frozen by interstitial impurities. No differentiation was made between the behavior of steel after a quench and after a high-temperature thermomechanical treatment, respectively, so that differences in the low-temperature diagrams could be related to the peculiarities of nonthermal deformation and to the resistance to brittle fracture.

Effect of chemical composition on the low-temperature discontinuous plastic deformation of some nichrome steels

Effect of chemical composition on the low-temperature discontinuous plastic deformation of some nichrome steels

A theory for the low-temperature plastic deformation of glassy polymers

Abstract A theory of yielding of glassy polymers by thermally-activated production of local molecular kinks is described. It is possible to obtain the activation free enthalpy of this process by modeling the intermolecular energy barrier as resulting from the stress fields of two equal and opposite closely spaced wedge disclination loops extending over the molecular cross section at the points of rotation of the molecular kinks. The theory predicts the yield stress at absolute zero to be dependent only on the shear modulus and the Poisson's ratio, and is capable of describing the temperature, pressure, and strain rate dependences of the flow stress from absolute zero to near the glass transition temperature. Comparison of the theory with the available experimental, results on polystyrene, polyethylene-terephthalate, polycarbonate of bisphenol A, and poly-methyl-methacrylate shows excellent agreement in nearly all respects.

Mechanism of the low temperature plastic deformation in zinc single crystals

physica status solidi (a)Volume 10, Issue 2 p. K113-K115 Short Note Mechanism of the low temperature plastic deformation in zinc single crystals Ya. M. Soifer, Ya. M. Soifer Academy of Sciences of the USSR, ChernogolovkaSearch for more papers by this authorV. G. Shteinberg, V. G. Shteinberg Academy of Sciences of the USSR, ChernogolovkaSearch for more papers by this author Ya. M. Soifer, Ya. M. Soifer Academy of Sciences of the USSR, ChernogolovkaSearch for more papers by this authorV. G. Shteinberg, V. G. Shteinberg Academy of Sciences of the USSR, ChernogolovkaSearch for more papers by this author First published: 16 April 1972 https://doi.org/10.1002/pssa.2210100240Citations: 6AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article.Citing Literature Volume10, Issue216 April 1972Pages K113-K115 RelatedInformation

Recovery of the electrical resistivity of duraluminium plastically deformed at 77°k

Abstract Abstract Basing ourselves on the assumption that the changes in the electrical resistivity of polycrystalline duraluminium in the process of a low temperature plastic deformation and a following annealing in the temperature interval 300–360°K can be given by the relation: , the process of formation of an S phase, which leads to a change of the effective cross section of electron scattering, is analysed. It is shown that the results comply with the scheme of forming of an S phase, proposed by Stegoleva and Bouinov (1967). The coefficient is determined.

Determination of Instantaneous Heat Sources with Inert Thermometers

The temperature transients arising from instantaneous plane heat sources in a linear heat conductor are analyzed. The thermal conductivity and the specific heat of the conductor are assumed to be temperature independent. Two thermometers are fastened to the conductor. The thermometers possess heat capacity causing inert response. It is found that the position and strength of a heat source can be calculated from the first and second time integral of the observed transient temperature difference between the two thermometers. If the inertia parameter is large, the thermometer heat capacity can be derived from the response to a uniform short heat pulse. The method can be applied to problems of low-temperature plastic deformation and superconductivity. An experimental example is discussed, in which instantaneous plane heat sources are generated by localized discontinuous tensile deformation at 4.2°K. The positions of the slipped zones and the amount of heat released during each slip are determined.

Dislocation damping in copper after low temperature plastic deformation

Dislocation damping in copper after low temperature plastic deformation

Production and Mobility of Point Defects in Titanium and Zirconium

ELECTRICAL resistivity measurements have been made by many workers on quenched, irradiated or plastically deformed metals, in order to study the production of defects by these various treatments. By observing the recovery of the resistivity on annealing, it is possible to study the mobility of the various defects out of the material or to internal sinks. In this communication we present some results on the mobility of defects, introduced by low-temperature plastic deformation in titanium and zirconium.

Effect of Low-Temperature Plastic Deformation upon the Optical Properties of Alkali Halides

Effect of Low-Temperature Plastic Deformation upon the Optical Properties of Alkali Halides

The instability of plastic flow of metals at very low temperatures

The low-temperature unstable plastic deformation of aluminium alloys is described. It is shown that discontinuities in the stress-strain curve are caused by a localized temperature rise produced during the deformation. The calculated magnitudes of the drops in load and the transition temperature between smooth and discontinuous flow agree reasonably well with the experimental observations. It is believed that all metals should exhibit unstable deformation at sufficiently low temperatures.