High strength plated steel wire for aerial transmission line reinforcement, method for producing steel stranded wire, and steel wire and steel stranded wire produced thereby

摘要

The invention provides a plated metal wire and steel strand for overhead transmission line reinforcement and a manufacturing method. The manufacturing method of the plated steel wire includes the steps of: performing wire drawing on steel to manufacture a steel wire, the steel containing 0.9 to 1.2 wt% of carbon, 1.0 to 1.5 wt% of silicon, 0.4 to 0.6 wt% of manganese, 0.2 to 0.7 wt% of chromium, less than 0.015 wt% but not including 0% of sulfone, less than 0.015 wt% but not including 0% of phosphorus, iron as a residual part and inevitable impurities; performing primary plating on the steel wire in a galvanizing bath to form an iron-zinc alloy layer and a zinc coating formed on the iron-zinc alloy layer; performing secondary plating in a zinc-aluminum plating bath, so as to modify the iron-zinc alloy layer into an iron-zinc-aluminum alloy layer and modify the zinc coating into a zinc-aluminum alloy layer; and forming a plated steel wire whose iron-zinc-aluminum alloy layer has a thickness of 40% to 60% of the sum of the thickness of the iron-zinc-aluminum alloy layer and the zinc-aluminum alloy layer. The plated metal wire and steel strand are high in strength and low in resistance, thereby providing an effect of being capable of reducing electric power loss.