The invention relates to a preparation method of
martensite matrix 1,100-MPa-grade
rare earth Q and P steel. The steel is prepared from 0.15-0.22% of C, 0.60-1.70% of Si, 1.10-2.40% of Mn, 0.1-0.5% ofMo, 0.1-0.5% of Al, 0.05-0.11% of V, 0.01-0.05% of Y, 0.02-0.04% of P, 0.005% or below of S, 0.040-0.0700% of Nb, 0.0060% or below of N, 0.001-0.006% of B and the balance Fe and unavoidable impurities. After batching, the raw materials are smelt by a converter and refined and continuously cast by a
vacuum furnace to obtain a cast blank, then trace
alloy powder is added into an arc-
melting furnace, a secondary cast blank is obtained, and heating and hot rolling are conducted in sequence; cold rolling is conducted after acid
pickling; then the blank is heated to a two-phase region for heat preservation; carbon partitioning and
tempering are conducted to obtain the final steel. According to the preparation method, through the addition of an appropriate quantity of various beneficial
alloy elements, the contents of C, Si, Mn and other elements in traditional steel species are reduced, the
weldability and
corrosion resistance are improved,
crystal grains are refined, produced steel plateshave good comprehensive mechanical properties, and lightweight,
energy conservation and emission reduction of vehicles are facilitated.