Search International and National Patent Collections
|1. (WO2017069161) HOT-ROLLED STEEL AND STEEL PART|
|Applicants:||NIPPON STEEL & SUMITOMO METAL CORPORATION
|Title:||HOT-ROLLED STEEL AND STEEL PART|
Hot-rolled steel according to an embodiment of the present invention has a prescribed chemical composition that includes 0.0001–0.0050 mass% of Bi; at least 90% by area of the metal structure consists of ferrite and pearlite; and the average number density of manganese sulfides, as measured at a cross-section parallel to the rolling direction, having an equivalent circle diameter of 1–5 μm and having an aspect ratio stretched along the rolling direction of more than 10 but less than or equal to 30 is 50–200/mm2.