CORROSION-PROOF HIGH-STRENGTH NON-MAGNETIC STEEL AND METHOD OF THERMAL DEFORMATION PROCESSING OF SUCH STEEL Russian patent published in 2010 - IPC C22C38/58 C21D8/02 C21D8/12 

FIELD: metallurgy.

SUBSTANCE: ingot of corrosion-proof high-strength non-magnetic steel containing, wt %: carbon 0.02-0,06, silicon 0.10-0.60, manganese 9.5-12.5, chrome 19.0-21.0, nickel 4.5-7.5, molybdenum 1.2-2.0, vanadium 0.08-0.22, calcium 0.005-0.010, sodium 0.005-0.010, niobium 0.05-0.15, magnesium 0.0005-0.001, nitrogen 0.40-0.60, aluminium 0.005-0.01, sulphur 0.003-0.012, phosphor 0.004-0.025, lead 0.0002-0.005, bismuth 0.0002-0.005, tin 0.0002-0.005, arsenic 0.0002-0.005, copper 0.05-0.2, iron the rest, is heated and deformed to form a plate in temperature range of 1240-1000°C with total deformation degree of 40-94%. The plate is cooled in the air for surface finish quality inspection and cleaning. Obtained plate undergoes deformation within temperature range of 1240-1000°C with fixation of total deformation degree at 45-65% level by 10-14% per pass, to form a sheet of thickness 2.5-3.5 times smaller than plate thickness. The sheet obtained is cooled in the air to 1000-950°C with surface temperature control. Final deformation is performed in 2-3 passes by 8-12% per pass, with further accelerated cooling down at 10-50°C/second rate to 100-150°C at the sheet surface and further cooling in the air.

EFFECT: enhanced durability and plasticity characteristics, impact strength, low magnetic inductivity.

2 cl, 4 tbl, 1 ex