PSI - Issue 6

Svetlana Atroshenko et al. / Procedia Structural Integrity 6 (2017) 259–264 Author name / Structural Integrity Procedia 00 (2017) 000 – 000

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The obtained results made it possible to receive data on the dynamic limit of elasticity of the magnesium alloy  el =205  5 MPa, as well as the spall strength of the alloy  sp =805  5 MPa, which does not substantially distinguish the strength of this alloy from aluminum alloys at much lower density (  =1,77 g/cm 3 ). After loading by exploding conductors, the grain size decreased, although the spread remained significant (Table 1). Figure 5 shows the structure of the magnesium samples after impact loading. Dynamic recrystallization regions of round shape are observed, within which the grain size is smaller than in the rest of the material (a, b). In contrast to traditional structural metals, in which the area of spallation (spall slit) is characterized by a main crack, in the samples of magnesium alloy, the spallation region is a chain of cavities, often not connected by microtracks - Fig. 5c, but in this range of impact intensity there is no separation of the "spall plate" in the samples.

a

b

c

Fig.5. Microstructure of magnesium alloy samples after loading by exploding of conductors.

4. Conclusion

The preliminary studies of the strength properties of the magnesium alloy AZ31B show high energy consumption, which goes to structural transformations in magnesium alloys during deformation. This effect, apparently, determines the sufficiently high strength of the magnesium alloy under shock loading. Thus, the conducted studies show the perspective of applications such light structural alloys in various fields of modern technologies. It should be noted that the selection of conditions for preliminary heat treatment and the use of methods of intensive plastic deformation of the initial alloy can significantly improve their strength properties.

Acknowledgements

This study was supported by the Russian Foundation for Basic Research jointly with the National Natural Science Foundation of China (RFBR-NSFC bilateral cooperation project no. 16-51-53006) and the Russian Science Foundation project No. 15-19-00182. The authors are grateful to the pupil of the Lyceum No 101 Nikolaeva Elena for help in processing the results of structural studies.

References

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