Rigid-Plastic Beams Under Uniformly Distributed Impulses

1965 ◽  
Vol 32 (3) ◽  
pp. 481-488 ◽  
Author(s):  
A. L. Florence ◽  
R. D. Firth
Keyword(s):  
Plastic Deformation ◽  
Strain Hardening ◽  
Large Deflections ◽  
Rigid Plastic ◽  
Clamped Beams ◽  
Plastic Theory

This paper contains the description and results of experiments in which pinned and clamped beams are subjected to uniformly distributed impulses large enough to cause considerable plastic deformation. The final permanent shapes are compared with those predicted by the rigid-plastic theory. They are also compared with the shapes predicted when the theory takes some account of large deflections and strain-hardening.

Plastic Deformation of Impulsively Loaded Straight Clamped Beams

1965 ◽  
Vol 32 (1) ◽  
pp. 7-10 ◽  
Author(s):  
John S. Humphreys
Keyword(s):  
Plastic Deformation ◽  
Beam Theory ◽  
Upper Bounds ◽  
Impulsive Loading ◽  
Steel Beams ◽  
Rigid Plastic ◽  
First Approximation ◽  
Ballistic Pendulum ◽  
Clamped Beams ◽  
Flat Steel

A series of tests was conducted on flat steel beams of various sizes and material properties, using sheet explosive to provide sufficiently high uniform impulsive loading to produce significant plastic deformation. The beams were attached to a ballistic pendulum for measurement of applied impulse, and were photographed with a Fastax camera during deformation. The resulting final deformations are compared with the rigid-plastic theory of Symonds and Mentel, which is seen to give upper bounds that are in general higher by about 20–30 percent than the deformations observed. A fairly good first approximation to maximum deflection for engineering purposes is in fact obtained simply by using rigid-plastic beam theory (including axial constraints).

Experimental and Theoretical Investigation of the Plastic Deformation of Cantilever Beams Subjected to Impulsive Loading

1962 ◽  
Vol 29 (4) ◽  
pp. 719-728 ◽  
Author(s):  
S. R. Bodner ◽  
P. S. Symonds
Keyword(s):  
Plastic Deformation ◽  
Aluminum Alloy ◽  
Strain Rate ◽  
Yield Stress ◽  
Impulsive Loading ◽  
Cantilever Beams ◽  
Rigid Plastic ◽  
Impulsive Load ◽  
Velocity Change ◽  
Plastic Theory

The experimental techniques and the results obtained in a program to evaluate the assumptions of dynamic, rigid-plastic theory of beams are presented. The experiments used steel and aluminum-alloy cantilever beams subjected to either a rapid velocity change at the base or to an impulsive load at the tip. A rigid-plastic theory that includes the strain-rate dependence of the yield stress and geometry changes is outlined for the case of the tip impulsive loading. The predictions of this theory are in satisfactory agreement with the experimental results.

Discussion of “Frame Instability and Strain Hardening in Plastic Theory”

1967 ◽  
Vol 93 (1) ◽  
pp. 587-596
Author(s):  
Peter F. Adams ◽  
Adel Helmy Salem ◽  
Anatol A. Eremin
Keyword(s):  
Strain Hardening ◽  
Plastic Theory

The Effect of Plastic Deformation on the Thermoelastic Constant and the Potential to Evaluate Residual Stress

2011 ◽  
Vol 70 ◽  
pp. 458-463 ◽  
Author(s):  
A. F. Robinson ◽  
Janice M. Dulieu-Barton ◽  
S. Quinn ◽  
R. L. Burguete
Keyword(s):  
Residual Stress ◽  
Plastic Deformation ◽  
Plastic Strain ◽  
Strain Hardening ◽  
Thermoelastic Stress ◽  
Paint Coating ◽  
Full Field ◽  
Thermoelastic Constant ◽  
Thermoelastic Response ◽  
Measured Change

In some metals it has been shown that the introduction of plastic deformation or strain modifies the thermoelastic constant, K. If it was possible to define the magnitude of the change in thermoelastic constant over a range of plastic strain, then the plastic strain that a material has experienced could be established based on a measured change in the thermoelastic constant. This variation of the thermoelastic constant and the ability to estimate the plastic strain that has been experienced, has potential to form the basis of a novel non-destructive, non-contact, full-field technique for residual stress assessment using thermoelastic stress analysis (TSA). Recent research has suggested that the change in thermoelastic constant is related to the material dislocation that occurs during strain hardening, and thus the change in K for a material that does not strain harden would be significantly less than for a material that does. In the work described in this paper, the change in thermoelastic constant for three materials (316L stainless steel, AA2024 and AA7085) with different strain hardening characteristics is investigated. As the change in thermoelastic response due to plastic strain is small, and metallic specimens require a paint coating for TSA, the effects of the paint coating and other test factors on the thermoelastic response have been considered.

Study of the Titanium Alloy Deformation Behavior in Equal Channel Angular Extrusion

2007 ◽  
Vol 345-346 ◽  
pp. 177-180 ◽  
Author(s):  
Dyi Cheng Chen ◽  
Yi Ju Li ◽  
Gow Yi Tzou
Keyword(s):  
Plastic Deformation ◽  
Titanium Alloy ◽  
Deformation Behavior ◽  
Equal Channel Angular Extrusion ◽  
Effective Strain ◽  
Processing Conditions ◽  
Rigid Plastic ◽  
Die Geometry ◽  
Extrusion Processing ◽  
Plastic Deformation Behavior

The shear plastic deformation behavior of a material during equal channel angular (ECA) extrusion is governed primarily by the die geometry, the material properties, and the processing conditions. Using commercial DEFORMTM 2D rigid-plastic finite element code, this study investigates the plastic deformation behavior of Ti-6Al-4V titanium alloy during 1- and 2-turn ECA extrusion processing in dies containing right-angle turns. The simulations investigate the distributions of the billet mesh, effective stress and effective strain under various processing conditions. The respective influences of the channel curvatures in the inner and outer regions of the channel corner are systematically examined. The numerical results provide valuable insights into the shear plastic deformation behavior of Ti-6Al-4V titanium alloy during ECA extrusion.

Sign in / Sign up

Export Citation Format

Share Document