| 摘要 |
FIELD: metallurgy. ^ SUBSTANCE: method involves passage of cold-rolled strip steel coil through bath with molten slag, cooled and rolled; at that, steel strip containing the following components is used, wt %: carbon 0.04 - 0.08, manganese 0.24 - 0.39, silicon 0.01 - 0.03, sulphur 0.013 - 0.09, phosphorus 0.001 - 0.017, up to 0.1 of chrome and nickel, which is zinc-plated by being passed through the above bath at temperature of Thot z.p.C, and at the speed Vhot z.p., m/s, which are determined based on empirically obtained parameters of hot zinc plating as per equations Thot z.p. = 480.63 - 0.015 âu.r.c + 12.73 Cequiv - 0.057 hot z.p. and Vhot z.p.=161.93 - 0.017 ây.s.+ 0.069 âu.r.h, where âu.r.c and ây.s.c - ultimate resistance and yield strength of cold-rolled metal, âu.r.h and h.r. - ultimate resistance and relative elongation of hot-rolled strip, and Cequiv - carbon equivalent equal to Cequiv = [C] + [Mn]/9 + [Si]/3; at that, [C], [Mn], [Si] - content of carbon, manganese and silicon in steel, wt %, and strip steel obtaining is provided with âu.r.h= 370 - 420 MPa and h.r. = 28 - 36 % with zinc coating with fine irregularities Ra = 0.4 - 0.7 mcm. ^ EFFECT: invention allows improving consumer properties of zinc-plated strip steel coil owing to optimising the parameters of zinc-plating process. ^ 1 ex |
