STEEL, PRODUCT MADE OUT OF THE STEEL AND THE METHOD OF ITS MANUFACTURE Russian patent published in 2006 - IPC C22C38/58 C22C38/54 C21D8/06 

FIELD: ferrous industry; production of stainless steel of the martensitic-austenitic class.

SUBSTANCE: the invention is pertaining to the field of ferrous industry, to production of stainless steel of the martensitic-austenitic class intended for manufacture of the high-loaded components working on twisting and bending under a dynamic loading in corrosive acid mediums having a high content of salts of alkaline and alkaline-earth metals, salts of nitrogenous acid and sulfuric acid, ions of chlorine and hydrogen sulfide. The steel contains the following ingredients(in mass %): Carbon - 0.005 - 0.07; silicon - no more than 1.0; manganese - no more than 1.8; chrome - 12.5 - 17.0; nickel - 2.0 - 8.0; molybdenum + 3 · tungsten - 0.05 - 5-4.5; nitrogen - 0.005 - 0.15; boron - 0.0001 - 0.01; at least one the following ingredients: aluminum, titanium, niobium, vanadium - 0.01 - 5.0; iron and impurities - the rest. At that Thus (Mo+3·W)≤(k_l-Cr·a_l), where k_l=15.9, a₁ = 0.87, and also_{Ni=k2-a2·(Cr+Mo+W), wherek2 = 16.25 ± l.5, a2=0.7 ± 0.l. The method of manufacture of the product provides for ingots casting or blanks continuous casting, rolling and thermal treatment. The technical result of the invention is an increased steel plasticity, its corrosion resistance in hydrosulfuric mediums with a simultaneous increase of stability of the steel mechanical properties.}

EFFECT: the invention ensures an increased steel plasticity, corrosion resistance in hydrosulfuric mediums, stability of the steel mechanical properties.

25 cl, 2 tbl, 1 ex