FIELD: metallurgy.
SUBSTANCE: group of inventions includes a method of making a flat steel product from steel, a flat steel product and its use. It can be used in automotive industry, construction of railway transport, shipbuilding, production of equipment, construction, mining, aerospace industry, production of household appliances or for thin-sheet welded composite workpieces. Flat product from steel with average content of manganese 4–12 %, having TRIP/TWIP-effect, is obtained by cold rolling of hot-rolled strip, subsequent annealing at temperature of 500–840 °C for 1 minute to 24 hours and leveling rolling of annealed strip with deformation degree from 0.3 to 60 %.
EFFECT: higher resistance to delayed formation of cracks induced by hydrogen, to hydrogen embrittlement and to liquid metal embrittlement during welding in galvanized state.
13 cl
