Effect of deformation and short-term high-temperature annealing on the microstructure and mechanical properties of austenitic steel Cr17Ni14М3

The effect of plastic deformation and short-term high-temperature annealing on the features of the microstructure and mechanical properties of stable chromium-nickelaustenitic steel was studied. It is shown that under conditions of deformation microtwin packets and localized deformation bands with internal fragmented structureconsisting of submicro- and nanosized fragments with low and high angle misorientation boundariesare formedin steel.These features of the microstructure provide high yield strength of ≈ 1100 MPa, with a relative elongation of ≈ 6 - 7%. Short-term (up to 150 s) high-temperature (850 ºС) cyclic annealing of the deformed microstructure leads to the local development of polygonization and recrystallization processes in the areas of localized deformation bands.As a result of such annealing, microtwins packets, localized deformation bands, polygonized subgrains and recrystallized grains of predominantly submicron size are observed in the steel structure. The obtained structural states provide the yield strength values up to ≈ 740 MPa with a relative elongation of ≈ 20 - 28%. The physical processes occurring in the steel under the studied conditions of deformation and annealing are discussed.

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