Disclosed are a 60kg-level low-cost and high-
toughness steel plate and a production method thereof. The 60kg-level low-cost and high-
toughness steel plate comprises, in weight percentage, 0.145%-0.185% of C, not less than 0.30% of Si, 1.35%-1.65% of Mn, not less than 0.013% of P, not less than 0.003% of S, not less than 0.25% of Cu, not less than 0.25% of Ni, 0.005%-0.015% of AlS, 0.150%-0.190% of V, 0.015%-0.020% of N, 0.001%-0.003% of Ca, and the balance of Fe and unavoidable impurities. Based on an alloyed component
system of medium C, low Si, high Mn, ultralow AlA and high V with metallurgical technical control, RCR-NT (recrystallization controlled rolling-normalized
tempering) processes are optimized, the
microstructure of the finished steel plate includes even and small ferrite,
pearlite and trace granular
bainite, average grain size of the ferrite is smaller than 15 micrometers, even and fine match of high
toughness and high
plasticity is obtained, and the steel plate has extremely fine low-temperature toughness. The steel plate is especially applicable to large-sized steel structured containers, such as bearing components,
petroleum storage tanks, mobile tankers and the like.