The invention relates to
alloy steel for a high-pressure container. The
alloy steel comprises the following components in percentage by weight: 0.27 to 0.33 percent of C, 0.60 to 1.00 percent of Mn, 1.40 to 1.70 percent of Si, less than or equal to 0.003 percent of S, less than or equal to 0.006 percent of P, 0.80 to 1.20 percent of Cr, 0.30 to 0.50 percent of Mo, 0.10 to 0.15 percent of V and the balance of Fe and inevitable impurities, wherein the total content of
impurity elements and gas, namely, S+P+H+O+N is less than or equal to 100 ppm. In the
smelting process of the invention, the form of electric furnace or electric furnace and electroslag remelting is replaced by the form of
vacuum induction furnace and consumable
electrode vacuum furnace, so that the problem of low
toughness, particularly low
fracture toughness caused by the low
impurity of an original type of steel; in a
processing procedure, high-speed
forging or steam hammering of which the
processing ratio is more than 5 is replaced by high-speed
forging and
radial forging of which the
processing ratio is more than 10, so that the problems of non-uniform grain size and structure caused by non-uniform
forging of the original type of steel are solved; and in a thermal refining process, the form of
quenching and high temperature
tempering is replaced by the form of
quenching and low temperature
tempering, and the sorbite structure of the original type of steel is replaced by a
martensite structure, so that the problem of insufficient intensity is solved.