Nippon Steel Sumitomo Metal Corporation

Yuji Tomimasu

Kenichi Nakamura

Masashi Sakamoto

Junichi Kodama

Akira Nishida

Osamu Ooyama

A rolled wire rod includes, as a chemical component, by mass %, C: 0.95% to 1.10%, Si: 0.10% to 0.70%. Mn: 0.20% to 1.20%, and Cr: 0.90% to 1.60%, the balance consisting of Fe and unavoidable impurities, in which a metallographic structure of the rolled wire rod includes, by an area ratio, 90% to 100% of pearlite, 0% to 5% of proeutectoid cementite, and 0% to 10% of degenerate pearlite having granular cementite, an average size of a pearlite block of the pearlite is 1.0 &#x3bc;m to 15 &#x3bc;m, and a maximum size of the pearlite block is 1 to 4 times the average size.

Growing community of inventors

Tokyo, Japan

Yuji Tomimasu