1.1.9 Necking of a round tensile bar

Products: ABAQUS/Standard  ABAQUS/Explicit  

This example illustrates necking and softening of a round tensile bar. This problem has been studied by Needleman (1972), Tvergaard and Needleman (1984), Needleman and Tvergaard (1985), and Aravas (1987). The material is assumed to be a rate-independent metal in which triaxial tension stress can allow voids to nucleate and grow. The example illustrates the use of the *POROUS METAL PLASTICITY model and the *VOID NUCLEATION suboption. In ABAQUS/Explicit the *POROUS FAILURE CRITERIA suboption is used to model failure of the material after a critical void volume fraction is reached.

Problem description

Results and discussion

Input files

References

Figures

Figure 1.1.9–1 Geometry and mesh for the round tensile bar.

Figure 1.1.9–2 Overall nominal stress, , vs. overall nominal strain, .

Figure 1.1.9–3 Void volume fraction at 19% (ABAQUS/Standard).

Figure 1.1.9–4 Hydrostatic pressure at 19% (ABAQUS/Standard).

Figure 1.1.9–5 Void volume fraction at 19.75% (ABAQUS/Standard).

Figure 1.1.9–6 Hydrostatic pressure at 19.75% (ABAQUS/Standard).

Figure 1.1.9–7 Total void volume fraction at 22.88% (ABAQUS/Explicit).

Figure 1.1.9–8 Hydrostatic pressure at 22.88% (ABAQUS/Explicit).

Figure 1.1.9–9 Final broken bar and its initial configuration (ABAQUS/Explicit).

Figure 1.1.9–10 Hydrostatic pressure in the broken bar (ABAQUS/Explicit).