STEEL MATERIAL COATED WITH ZINC-BASED ALLOY OF HIGH CRACKING RESISTANCE OWING TO EMBRITTLEMENT BY FUSED METAL Russian patent published in 2014 - IPC C22C38/14 C23C2/06 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, particularly to steel sheet with zinc-based alloy coat wherein parent material represents a low-carbon steel. Said steel features the following chemical composition, in wt %: C: 0.010-0.10, Si: not over 1.50, Mn: not over 2.00, P: not over 0.10, S: not over 0.030, N: not over 0.0050, Ti: not over 0.050 and B: 0.0003-0.010, Fe and unavoidable impurities making the rest. It features the magnitude of index L describing the interrelation between titanium content and nitrogen content with content of free boron and calculated by formula L={(Ti/48)+(B/11)}/(N/14) making at least 5.50. Sheet features metallographic structure containing ferrite: 10-99 wt %, bainite, perlite, cementite or martensite making the rest.

EFFECT: high cracking resistance and machinability by pressure.

4 cl, 3 dwg, 3 tbl, 3 ex