PROCESS OF THERMOMECHANICAL TREATMENT OF PRODUCTS OF AUSTENITE STEEL Russian patent published in 1994 - IPC

FIELD: metallurgy. SUBSTANCE: the process of thermomechanical treatment of products of austenite Cr-Mn-Ni steel comprises (wt %): 0.2-0.45 nitrogen; 0.5-1.2 vanadium or 0.1-0.4 niobium. The process comprises heating products to 1100-1150 C, keeping and cooling them to 630-650 C by using hot water, rolling the products at the temperature given above at a deformation degree of 60-80 %, subsequently cooling the products first in water and then in liquid nitrogen and immediately rolling the products once again at a deformation degree of 40-60 % , finally heating and keeping the products at 630-680 C and subsequently cooling them in water or in the air. The products thus treated have improved mechanical properties while retaining the level of plasticity due to the matrix structure having a particle size of austenite in the range from 0.1 to 0.2 micron and of carbonitrides in the range from 0.005 to 0.01 micron, their volumetric content being 20-30 %. EFFECT: greater efficiency of the process. 1 tbl