Topic
Necking
About: Necking is a research topic. Over the lifetime, 5280 publications have been published within this topic receiving 113945 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, a method is developed to determine the conditions for the onset of localized failure of carbon nanotubes by the singularity point of the acoustic tensor derived from a continuum energy function based on Tersoff-Brenner potential.
36 citations
Patent•
01 Jul 1991TL;DR: In this paper, a spin-flow die-necking operation was proposed to reduce plug diameter variability, thereby enhancing and complimenting the spinflow necking operation. But the spin-freeness of the die-nosing operation was not considered.
Abstract: The present invention is directed to a novel processing for necking metal container bodies. The process comprises die-necking a container body to a first necked plug diameter, employing one or more operations, and thereafter spin-flow necking the container body to a second reduced plug diameter. The utilization of die-necking advantageously reduces plug diameter variability, thereby enhancing and complimenting the spin-flow necking operation.
36 citations
TL;DR: In this paper, low-velocity impact tests were performed on dual-phase and martensitic steel sheets and compared with corresponding quasi-static tests, and the results in terms of force-displacement curves and strain histories at critical positions in the specimens were similar for low velocity and quasistatic loading, independent of material and specimen geometry.
36 citations
TL;DR: In this paper, an enhanced 2-D plane stress finite element model, where the thickness effect is taken into account by an incorporated length scale, is incorporated in the continuum description by a finite strain version of a gradient dependent J 2 -flow theory.
Abstract: Necking and post-necking of a uniaxially stretched tensile test specimen with a rectangular cross-section is investigated. The analysis is based on an enhanced 2-D plane stress finite element model, where the third dimension (the thickness effect) is taken into account by an incorporated length scale. The length scale, fixed with respect to the current deformed state, is incorporated in the continuum description by a finite strain version of a gradient dependent J 2 -flow theory. A convincing agreement with the true 3-D post-necking behaviour is obtained by this approximative 2-D plane stress model. The model gives a realistic prediction of the development of the post-necking zone in the tensile bar. Furthermore, the model is found to capture the transition from a dominating diffuse necking mode for a tensile bar with a square cross section to a dominating oblique localised necking mode for a wide strip; effects which can not be captured by an analysis based on a conventional (local) plane stress model.
36 citations
TL;DR: In this article, a series of matched tensile specimens of aluminum-killed steel sheet were used to measure the continuous strain-rate sensitivity,m====== c, in series of isothermal tests at different crosshead speeds, in contrast with the instantaneous strain sensitivity, mi, which was found to vary strongly with strain rate.
Abstract: Precisely machined tensile specimens of aluminum-killed steel sheet were used to measure the continuous strain-rate sensitivity,m
c, in a series of isothermal tests at different crosshead speeds.m
cwas found to be independent of strain and strain rate, in contrast with the “jump” test instantaneous strain sensitivity, mi, which was found to vary strongly with strain rate. A series of matched tensile specimens was also photogridded and deformed at three rates and terminated at four elongations. The strain distributions obtained from these tests were compared with Finite Element Modeling (FEM)—calculated ones based on several strain-rate sensitivity formulations. Comparison of calculations with experiments revealed that the operant rate sensitivity during tensile localization,m
t, was intermediate betweenm
candm
iat each rate and elongation. Once the effective rate sensitivity was established, detailed predictions of strain distributions and failure elongations agreed very well with experiment. A qualitative model of strain-based stress transients was proposed for both strain-rate and strain-state path changes.
36 citations