▎ 摘　　要

NOVELTY - Manufacturing high strength alloy steel bolt comprises (i) taking steel for the bolt, performing extrusion, hot upsetting, heat treatment and thread machining to obtain a bolt blank, and (ii) performing galvanizing and zinc-aluminum coating into the bolt blank to obtain the high strength bolt. The steel for bolt comprises ≤ 0.12% carbon, 0.021-0.025% niobium, 1.8-2 % nickel, 0.5-1 % molybdenum, 0.0008-0.0012% boron, 0.10-0.35% silicon, 0.60-0.90% manganese, ≤ 0.030% phosphorus, ≤ 0.030% sulfur, ≤ 0.0001% nitrogen and iron (remaining amount). USE - The method is useful for manufacturing high strength alloy steel bolt. ADVANTAGE - The method has excellent mechanical property, corrosion resistance and delayed fracture performance and controls the carbon and alloy elements in the steel for the bolt and processes e.g cold deformation, heat treatment, realizes the deformation strengthening, thinning strengthening, precipitation strengthening, and hydrogen trap. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is also included for high-strength alloy steel bolt manufactured by above method.