Influence of the structure on the deformation ability of the Fe-Cr-Co system alloys

The deformation behavior of two hard magnetic alloys 23X15KТ (Fe-23% Cr-15% Co) and 30X23K (Fe-30% Cr-23% Co) have been studied in the temperature range 800-1050 °C and strain rates 10^-1 - 10^-4 s^-1. The influence of two types of structures - ultrafinegrained and lamellar (α+γ in the 23Х15КТ alloy and γ+σ in the alloy 30Х23К) on the superplasticity characteristics of alloys was established. During tensile straining of the 30X23K alloy with a lamellar structure, the flow stress after 10% deformation is gradually decreased, while in the alloy 23X15K, on the contrary, the deformation proceeds with hardening. It is shown that the investigated alloys with an ultrafine-grained structure exhibit superplastic behavior both under tensile straining and upsetting deformation in the temperature range of 900-950 °С and deformation rates of 10^-2 - 10^-4 s^-1.