Rolled H shape steel having uniform microstructure and uniform mechanical property and its manufacturing method

摘要

The present invention relates to an H-shaped steel used as a member for a building structure, and, in this H-shape steel, an H-shaped steel manufactured from a steel piece having a carbon equivalent CEQ = C + Si / 24 + Mn / 6 + Ni / 40 + Cr / 5 + Mo / 4 + V / 14 from a steel piece having a chemical composition of 0.15 to It is a uniform microstructure and a manufacturing method of the rolling H shape steel having a uniform mechanical property which satisfies one or more of the following microstructures based on the di portion as the reference. 1) the average value of ferrite particle size in microstructures is 1 / 2 flange and fillet parts within u00b1 15%. (2) the average value of ferrite particle size in microstructures is within u00b1 15% in the 1 / 2 web. 3) the average value of pearlite fraction in microstructures is within u00b1 8% of the 1 / 2 flange and fillet parts. 4) the average value of pearlite fraction in microstructures is within u00b1 8% in the 1 / 2 web.