Abrasion Resistant Steel Plate or Steel Sheet has excellent resistance to Stress Corrosion Cracking and Method for manufacture

摘要

Provides an Abrasion Resistant Steel Plate or Steel Sheet suitable for use in construction machinery, Industrial Machinery, and similarIt has excellent resistance to Stress Corrosion Cracking and a method to manufacture. A Steel Plate or Steel Sheet has a composition containing 0.20% to 0.27% of C, 0.05% to 1.0% si, 0. 30% to 1.56% Mn, P, S, 0.005% 0.025% NB, 0. 008% and 0.020% ti, 0.1% or less, and 0.0010% to 0.On the basis of 0.060% n% in Mass, the composition also contains one or more of CR, MO, W, and B, the composition contains one or more of cu, ni, V, a REM, CA, and mg as requiredThe rest is fe and inevitable impurities. Steel Plate or Steel Sheet has a di of 45 or more and a microstructure that has a phase base or main phase is Tempered martensite.Precipitates containing NB / TI which has a Grain size of 0.01 micromole to 0.5 micromol in terms of equivalent Circle diameter is present in the steel plate or Steel Plate 2 x 10 ^ 2 grains / mm2 or more.After being heated, a semi-finished product that has Composition of Steel Sheet in hot and is put off by overheating or direct off.