HIGH STRENGTH STRUCTURAL STEEL OF TENSILE STRENGTH OF 650MPA GRADE WITH LOW YIELD RATIO AND METHOD OF MANUFACTURING THE HIGH STRENGTH STRUCTURAL STEEL,申请号KR20100061548-传众专利搜索

HIGH STRENGTH STRUCTURAL STEEL OF TENSILE STRENGTH OF 650MPA GRADE WITH LOW YIELD RATIO AND METHOD OF MANUFACTURING THE HIGH STRENGTH STRUCTURAL STEEL

申请公布号：KR20120000987(A)

申请号：KR20100061548

申请日期：2010.06.29

申请公布日期：2012.01.04

申请人：

HYUNDAI STEEL COMPANY

发明人：HWANG, BYANG IL

分类号：C22C38/00;C21D8/02;C22C38/54

主分类号：C22C38/00

摘要：PURPOSE: A high-strength structural steel material having a low yield ratio and 650 MPa tensile strength and a manufacturing method thereof are provided to improve tensile strength by controlling cooling conditions after hot rolling. CONSTITUTION: A high-strength structural steel material having a low yield ratio and 650 MPa tensile strength comprises carbon 0.1-0.15 weight%, silicon 0.3-0.5 weight%, manganese 1.2-1.5 weight%, phosphorus less than 0.03 weight%, sulfur less than 0.015 weight%, vanadium 0.04-0.06 weight%, titanium 0.01-0.03 weight%, boron 0.04-0.06 weight%, niobium 0.035-0.045 weight%, nitrogen less than 0.015 weight%, iron and inevitable impurities. The tensile strength of the structural steel material is over 650MPa, and the yield strength is over 400 MPa.