High-strength, low-alloy and high-carbon steel wire rod and production method thereof

Abstract

The invention provides a high-strength, low-alloy and high-carbon steel wire rod and a production method thereof. The high-strength, low-alloy and high-carbon steel wire rod comprises the following components: 0.86-1.0 percent of carbon (C), 0.1-2.0 percent of silicon (Si), 0.3-1.0 percent of manganese (Mn), 0.1-1.0 percent of chromium (Cr), not greater than 0.020 percent of phosphorus (P), not greater than 0.015 percent of sulfur (S), not greater than 0.1 percent of inevitable impurities and the balance of ferrum. The production method comprises the following steps: (1) molten iron desulfuration pretreatment: sulfur content is controlled to be under 0.005 percent; (2) converter melting: phosphorus content in steel is not greater than 0.010 percent, and the temperature of converter final molten steel is 1570-1680 DEG C; (3) low-frequency (LF) refining: the temperature is 1550-1620 DEG C; (4) continuous casting: a low-superheat degree casting process system is used; the superheat degree of tundish molten steel is not greater than 25 DEG C; and the dimension of a casting blank is (200-400mm)*(300-500mm); and (5) tandem rolling and wire stock rolling: the diameter of the wire rod is 5.5-8mm, and the supercooling degree of the wire rod is 50-75 DEG C in the phase change process. In the wire rod produced by adopting the process of the invention, the tensile strength is not less than 1300MPa, the area reduction index is not less than 35 percent, and the drawing requirement of a user is met.

Description

technical field [0001] The invention belongs to low-alloy high-carbon steel technology, and in particular relates to a high-strength low-alloy high-carbon steel wire rod and a production method thereof. Background technique [0002] As we all know, for high-carbon steel wire rods, usually by increasing the carbon content of the wire rod, higher tensile strength of the wire rod is obtained. However, as the carbon content increases, abnormal structures such as reticular cementite tend to appear inside the wire rod. The appearance of these tissues is easy to cause wire breakage in the drawing process of the wire rod. [0003] The invention patent entitled "High Carbon Steel Wire Rod and Its Preparation Method" (Application No.: CN200910169807.7) provides a high carbon steel wire rod with a tensile strength above 1200MPa and an area shrinkage rate above 35% and its Preparation process, the wire rod contains basic components such as C, Si, Mn, Cr and V, and optional components ...

AI Technical Summary

Problems solved by technology

[0004] The tensile strength of the product of this patented technology is above 1200Mpa, but the wire rod contains alloy components such as Cr and V, which increases the cost of the wire rod

Moreover, the carbon content is only 0.77%-0.84%, which cannot meet the development needs of users for the continuous improvement of the carbon content of high-strength high-carbon steel wire rods