high-strength steel plate for acid-resistant pipes and production method, and high-strength steel pipe using high-strength steel plate for acid-resistant pipes

摘要

the present invention relates to a high strength steel plate for acid resistant tubing having superior hic resistance in a central segregation part and a surface layer part. this high-strength steel plate for acid-resistant piping is characterized by having a component composition that includes a prescribed amount of c, si, mn, p, s, al and ca with the remainder being fe and the inevitable impurities and hair fact that the hydrogen diffusion coefficient at the center of the plate thickness is 5.0 x 10-6 cm2 / s or more, the maximum vickers hardness hv 0.1 to 0.5 mm below the surface of the steel plate is 250 or less, and the tensile strength is 520 mpa or more.