An improved description of copper‐ and iron‐cylinder impact (Taylor) test results has been obtained through the use of dislocation‐mechanics‐based constitutive relations in the Lagrangian material dynamics computer program EPIC‐2. The effects of strain hardening, strain‐rate hardening, and thermal softening based on thermal activation analysis have been incorporated into a reasonably accurate constitutive relation for copper. The relation has a relatively simple expression and should be applicable to a wide range of fcc materials. The effect of grain size is included. A relation for iron is also presented. It also has a simple expression and is applicable to other bcc materials but is presently incomplete, since the important effect of deformation twinning in bcc materials is not included. A possible method of acounting for twinning is discussed and will be reported on more fully in future work. A main point made here is that each material structure type (fcc, bcc, hcp) will have its own constitutive beha...

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Dislocation-mechanics-based constitutive relations for material dynamics calculations

1. Stress and strain 2. Plasticity 3. Strain hardening 4. Plastic instability 5. Temperature and strain-rate dependence 6. Work balance 7. Slab analysis and friction 8. Friction and lubrication 9. Upper-bound analysis 10. Slip-line field analysis 11. Deformation zone geometry 12. Formability 13. Bending 14. Plastic anisotropy 15. Cupping, redrawing and ironing 16. Forming limit diagrams 17. Stamping 18. Hydroforming 19. Other sheet forming operations 20. Formability tests 21. Sheet metal properties.

Metal Forming: Mechanics and Metallurgy

Asymmetric single point incremental forming of sheet metal

The mechanics of penetration of projectiles into targets

Electromagnetic forming—A review

Impact loading of plates and shells by free-flying projectiles: A review

Metallic energy dissipating systems.

Plasticity for mechanical engineers

A thin wall tube, when axially compressed over a radiused die, either inverts, or buckles or tears. The phenomena associated with the external or internal inversion of tubes of aluminium, copper, mild steel and brass are described and load-tube shortening curves are presented for speeds of compression between 0·05 in/min and 20 in/min; some results for high speed compression using a drop hammer are also described.Thickness changes during inversion are reported and experiments to establish the effect of die angle and die radius on the inversion load are given.For the inside-out inversion of tube, a simple theoretical analysis to predict the steady inverting load and the optimum die radius for a strain hardening material is given, the basic assumption being that no change in the wall thickness takes place.

Characteristics of Inversion Tubes under Axial Loading

Large deformations of thin-walled circular tubes under transverse loading—II: Experimental study of the crushing of circular tubes by centrally applied opposed wedge-shaped indenters

W. Johnson

Papers

Impact loading of plates and shells by free-flying projectiles: A review

Metallic energy dissipating systems.

Plasticity for mechanical engineers

Characteristics of Inversion Tubes under Axial Loading

Large deformations of thin-walled circular tubes under transverse loading—II: Experimental study of the crushing of circular tubes by centrally applied opposed wedge-shaped indenters