STEEL FOR HIGH-TEMPERATURE CEMENTED GEAR SHAFT AND METHOD OF MAKING SUCH STEEL Russian patent published in 2024 - IPC C22C38/20 C22C38/28 C22C38/26 C22C38/24 C21D8/06 

FIELD: metallurgy.

SUBSTANCE: invention relates to production of steel for high-temperature cemented gear shaft. Steel for high-temperature cemented gear shaft contains the following chemical components in wt.%: 0.17–0.22 C, 0.05–0.35 Si, 0.80–1.40 Mn, 0.010–0.035 S, 0.80–1.40 Cr, 0.020–0.046 Al, 0.006–0.020 N, 0.002–0.030 Nb, 0.003–0.02 V, 0.01 or less Ti and 0.06–0.20 Cu. Content of Nb, V, Al, N and C satisfies the following condition: micro-alloying element coefficient r_M/H = (20 * [Nb] / 93 − [V] /51 + [A1] / 27) / ([N] / 14 + [C] / 120), wherein coefficient r_M/H is in range from 0.61 to 3.0.

EFFECT: obtained steel retains size and stability of austenite grain at high temperature, has narrow range of ability to hardening and is easily processed.

9 cl, 3 tbl, 8 ex