PSI - Issue 65

A.S. Smirnov et al. / Procedia Structural Integrity 65 (2024) 255–262 A.S. Smirnov, A.V. Konovalov,V.S. Kanakin and I.A. Spirina/ Structural Integrity Procedia 00 (2024) 000–000

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indicates intensive softening of the composite matrix at these thermomechanical loading parameters. At a temperature of 400 °C and a strain rate of 0.1 s 1 , the flow stress first increases, and then remains unchanged with increasing strain. This indicates that the rates of hardening and softening are equal at this strain rate. At a strain rate of at least 0.5 s 1 there is a peak on the flow stress curves. This indicates intensive softening of the composite matrix.

Fig. 4. The strain dependence of flow stress for temperatures of 300 ℃ (a), 400 ℃ (b), and 500 ℃ (c).

4. Conclusions

1. The structural-phenomenological model of flow stress used in this study can simulate with acceptable engineering accuracy the rheological behavior of the V95\3% TiC metal matrix composite in the temperature range from 300 to 500 °C at time-varying strain rates in the range between 0.1 and 5 s 1 . 2. The strain dependences of flow stress obtained by a structural-hierarchical model at constant strain rates indicate that softening actively occurs in the range of temperatures from 300 to 500 °C and strain rates from 0.1 to 10 s 1 , thus causing to the appearance of peaks and a steady-state section on the flow stress curve.

Acknowledgments

The work was financially supported by the RSF, project No. 22-29-00428.