Effect of the mechanism of decomposition of the solid solution during aging on the properties of steel 10Kh12N20T2Sh

Abstract

1. The mechanical properties of steel 10Kh12N20T2Sh vary with the mechanism of decomposition of the solid solution during aging. Discontinuous decomposition leads to lower hardness and strength characteristics of the steel. Continuous decomposition produces a better combination of mechanical properties at room and elevated (600°) temperatures. 2. Cold plastic deformation and heating before aging have a substantial effect on the mechanism of decomposition of the solid solution during aging. The largest number of sections of discontinuous decomposition is observed with aging after preliminary heating at 900°. 3. Intermediate heating at 1020° in the process of split cold plastic deformation (8–9%+4–5%) and subsequent aging (730° for 2 h+650° for 8 h) makes it possible to obtain the following properties: σb=119 kgf/mm2. (100 kgf/mm2 according to TU), σ02=101 kgf/mm2 (60 kgf/mm2 according to TU), δ=24% (20% according to TU) at 20°; σb=93 kgf/mm2 and δ=11% at 600°. 4. Quenching of the finished parts before aging is inexpedient.