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Introduction

Research last 20 years have shown that metallic materials with SMC (SMC) structure formed by methods of severe plastic deformation (SPD), differ substantially in their properties from the coarse-grained counterparts. In fact, we can talk about new materials that have high expectations in terms of practical application.

Characterizations SMC metals is important because the operation IAP, usually combined with a form-building operations, and metal forming heat treatment. Therefore, to design the entire process chain forming such materials, you must have an understanding of their properties in different stress-strain state (SSS).

1.Materials and methods research

The material was selected for the study next copper chemical composition (Table 1).

Table 1.Chemical composition of copper M3

Himsostav copper M3

From each sample was subjected to CE, two samples were obtained for tests: one on a twisting and stretching.

Eskizy samples for testing

Figure 1 Sketches of specimens for testing torsion (a) and tensile (b).

Tests in torsion and rupture, were carried out in accordance with GOST 3565-80 "Metals. Test Method for Torsion, "and GOST 1497-84" Methods for tensile tests ».

2. Results of the study

Foto installation

Figure 2 General view of the stand.

Fig. 3 shows a comparison of the results of tensile tests and torsion in the true coordinates. It is clear that for the coarse copper, to a deformation of order 1, the stress-strain in tension and torsion are quite close, which corresponds to the hypothesis of a "single flow curve." For copper-treated screw extrusion course of these curves differ dramatically, reflecting the sensitivity of the material to the form of loading.

Results tensile tests and kruchenie

Figure 3 - Comparison of the results of tensile tests and torsion in the true coordinates.

3.Conclusion

Analysis of the results suggests that the parameters of VAT should be considered when characterizing the mechanical properties of SMC materials and display it on the material science maps.V further tests are planned draft, to get the full VAT diagrmmy copper M3 submikrokristal state.

References

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