Nippon Steel Corporation

Nippon Steel Sumitomo Metal Corporation

Makio Kikuchi

Seiki Nishida

Shingo Yamasaki

The invention provides wire rod excellent in drawability and steel wire made from the wire rod as starting material with high productivity at good yield and low cost. A hard steel wire rod of a specified composition is hot rolled, the hot-rolled steel is coiled in a specified temperature range, and the coiled steel is subjected to patenting at a predetermined cooling rate, thereby affording a high-carbon steel wire excellent in workability. It is high-strength steel wire excellent in drawability comprising a pearlite structure of an area ratio of 97% or greater and the balance of non-pearlite structures including bainite, degenerate-pearlite and pro-eutectoid ferrite and having a pearlite block size of not less than 20 &#x3bc;m and not greater than 45 &#x3bc;m. The invention also provides a high-carbon steel wire excellent in ductility, which is manufactured by subjecting the wire rod to intermediate patenting and cold drawing and has a tensile strength of 2800 MPa or greater.

High-strength wire rod excellent in drawing characteristics and method of manufacturing the same

The invention provides wire rod excellent in drawability and steel wire made from the wire rod as starting material with high productivity at good yield and low cost. A hard steel wire rod of a specified composition is heated in a specified temperature range to conduct post-reaustenization patenting and thereby obtain a high-carbon steel wire excellent in ductility that has a pearlite structure of an area ratio of 97% or greater and the balance of non-pearlite structures including bainite, degenerate-pearlite and pro-eutectoid ferrite and whose fracture reduction of area RA satisfies Expressions (1), (2) and (3) below:RA&#x2267;RAmin&#x2003;&#x2003;(1),

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Tokyo, Japan

Makio Kikuchi